{"id":33,"date":"2014-03-17T13:54:06","date_gmt":"2014-03-17T13:54:06","guid":{"rendered":"https:\/\/sites.ifi.unicamp.br\/modelogrupo\/?page_id=33"},"modified":"2019-08-28T17:20:54","modified_gmt":"2019-08-28T20:20:54","slug":"publicacoes","status":"publish","type":"page","link":"https:\/\/sites.ifi.unicamp.br\/lmd\/publicacoes\/","title":{"rendered":"Publica\u00e7\u00f5es"},"content":{"rendered":"<p><strong>Destaques das Publica\u00e7\u00f5es Cient\u00edficas do LMD<\/strong><\/p>\n<p>1)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-108 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A2-300x126.jpg\" alt=\"\" width=\"656\" height=\"276\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A2-300x126.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A2.jpg 567w\" sizes=\"auto, (max-width: 656px) 100vw, 656px\" \/><\/p>\n<p>Neste trabalho reportamos uma forte resposta piezoel\u00e9trica de grafeno de mono-camada depositado em em substratos de Si\/SiO<sub>2<\/sub>. Esta atividade piezoel\u00e9trica em camadas de grafeno foi atribu\u00edda as intera\u00e7\u00f5es qu\u00edmicas dos \u00e1tomos de grafeno com o oxig\u00eanio subjacente proveniente do substrato de SiO<sub>2<\/sub>. E a magnitude desta atividade \u00e9 suficientemente alta, mais do que duas vezes quando comparadas com as melhores cer\u00e2micas piezoel\u00e9tricas tais como zirconato titanato de chumbo modificados. Esta descoberta projeta aplica\u00e7\u00f5es emergentes para sensores e atuadores.<\/p>\n<p>2) <img loading=\"lazy\" decoding=\"async\" class=\" wp-image-114 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A4-300x143.jpg\" alt=\"\" width=\"533\" height=\"254\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A4-300x143.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A4-750x359.jpg 750w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A4.jpg 754w\" sizes=\"auto, (max-width: 533px) 100vw, 533px\" \/><\/p>\n<p>Nesta correspond\u00eancia, n\u00f3s respondemos ao coment\u00e1rio de Stampfer e Reichard sobre o c\u00e1lculo superestimado da deforma\u00e7\u00e3o no-plano. No entanto, isso n\u00e3o muda a conclus\u00e3o principal do artigo que \u00e9 a observa\u00e7\u00e3o experimental de forte piezoeletricidade em grafeno\/SiO<sub>2<\/sub>. Enfatizamos que, enquanto uma intera\u00e7\u00e3o inomog\u00eanea entre grafeno e substrato de SiO<sub>2<\/sub> subjacente (causada, por exemplo, pela morfologia do substrato) pode ser respons\u00e1vel pela deforma\u00e7\u00e3o no plano observada nas medidas de Raman, a resposta piezoel\u00e9ctrica observada \u00e9 atribu\u00edda \u00e0 forma\u00e7\u00e3o de liga\u00e7\u00f5es polares C-O fora do plano que podem n\u00e3o estar diretamente relacionadas a deforma\u00e7\u00e3o no plano.<\/p>\n<p>3)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-112 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A3-300x92.jpg\" alt=\"\" width=\"535\" height=\"164\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A3-300x92.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A3-750x232.jpg 750w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A3.jpg 755w\" sizes=\"auto, (max-width: 535px) 100vw, 535px\" \/><\/p>\n<p>Neste trabalho relatamos um estudo sobre o grafite, uma pilha macrosc\u00f3pica de camadas de grafeno, que estabelece uma liga\u00e7\u00e3o fundamental entre a dimensionalidade de um sistema eletr\u00f4nico e sua resposta Nernst. Em flagrante contraste com o caso de camada \u00fanica, o sinal de Nernst atinge o pico sempre que um n\u00edvel de Landau atinge o n\u00edvel de Fermi. Portanto, os graus de liberdade fornecidos pelo acoplamento finito intercamadas leva \u00e0 um aumento da resposta termoel\u00e9trica nas proximidades do limite qu\u00e2ntico. Como a quantiza\u00e7\u00e3o de Landau corta uma superf\u00edcie tridimensional de Fermi, cada intersec\u00e7\u00e3o de um n\u00edvel de Landau com o n\u00edvel de Fermi modifica a topologia da superf\u00edcie de Fermi. De acordo com esses resultados, a assinatura mais proeminente desta transi\u00e7\u00e3o de fase topol\u00f3gica emerge na resposta termoel\u00e9trica transversal.<\/p>\n<p>4)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-116 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A5-300x55.jpg\" alt=\"\" width=\"616\" height=\"113\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A5-300x55.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A5.jpg 633w\" sizes=\"auto, (max-width: 616px) 100vw, 616px\" \/><\/p>\n<p>Neste trabalho realizamos medidas de magneto-transporte em amostras de grafite HOPG at\u00e9 B = 50 T em campos magn\u00e9ticos pulsados em colabora\u00e7\u00e3o com o LNCMI-Toulouse-Fran\u00e7a. O resultado principal que obtivemos foi a primeira observa\u00e7\u00e3o do efeito Hall qu\u00e2ntico fracion\u00e1rio em grafite\/grafeno. Os nossos resultados sugerem que o efeito Hall qu\u00e2ntico fracion\u00e1rio est\u00e1 associado com um l\u00edquido qu\u00e2ntico do tipo 2\u00e9 de b\u00f3sons que implica na forma\u00e7\u00e3o de pares de Cooper no limite ultra qu\u00e2ntico.<\/p>\n<p>5)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-120 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A6-300x66.jpg\" alt=\"\" width=\"523\" height=\"115\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A6-300x66.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A6.jpg 511w\" sizes=\"auto, (max-width: 523px) 100vw, 523px\" \/><\/p>\n<p>Neste trabalho estudamos os coeficientes de transporte de um cristal \u00fanico de bismuto at\u00e9 um campo magn\u00e9tico m\u00e1ximo de 33 tesla, que \u00e9 intenso no limite ultraqu\u00e2ntico. O coeficiente Nernst apresenta tr\u00eas m\u00e1ximos inesperados que s\u00e3o concomitantes com os quasi-plat\u00f4s do coeficiente Hall. Os resultados sugerem que este material pode hospedar um fluido qu\u00e2ntico ex\u00f3tico reminiscente daquele associado com o efeito Hall qu\u00e2ntico fracion\u00e1rio e levantar a quest\u00e3o do fracionamento de el\u00e9trons em um metal tridimensional.<\/p>\n<p>6)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-122 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A7-300x93.jpg\" alt=\"\" width=\"513\" height=\"159\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A7-300x93.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A7-768x238.jpg 768w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A7.jpg 897w\" sizes=\"auto, (max-width: 513px) 100vw, 513px\" \/><\/p>\n<p>Neste trabalho \u00e9 feita uma breve revis\u00e3o geral dos desenvolvimentos recentes na \u00e1rea de pesquisa do grafeno, focando especialmente nas propriedades eletr\u00f4nicas do grafite. Evid\u00eancias experimentais indicam que o grafite de alta qualidade \u00e9 um sistema multicamadas com planos de grafeno 2D quase desacoplados. Com base em observa\u00e7\u00f5es experimentais, antecipamos que as amostras de grafite fina e n\u00e3o as camadas \u00fanicas ser\u00e3o as candidatas mais promissoras para o desenvolvimento de dispositivos eletr\u00f4nicos baseados em grafeno.<\/p>\n<p>7)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-124 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A8-300x74.jpg\" alt=\"\" width=\"591\" height=\"146\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A8-300x74.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A8-750x187.jpg 750w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A8.jpg 762w\" sizes=\"auto, (max-width: 591px) 100vw, 591px\" \/><\/p>\n<p>Neste trabalho, relatamos o primeiro estudo de termoeletricidade met\u00e1lica no limite qu\u00e2ntico. A principal resposta termoel\u00e9trica \u00e9 fora da diagonal com um componente oscilante muitas vezes maior que o background n\u00e3o oscilante. Quando o primeiro n\u00edvel de Landau atinge a energia de Fermi, ambos os coeficientes de Nernst e Ettingshausen atingem um pico acentuado, e este \u00faltimo atinge um m\u00e1ximo independente da temperatura. Notamos um acordo qualitativo com uma teoria que invoca excita\u00e7\u00f5es de borda de transporte de corrente.<\/p>\n<p>8)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-127 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A9-300x76.jpg\" alt=\"\" width=\"592\" height=\"150\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A9-300x76.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A9.jpg 764w\" sizes=\"auto, (max-width: 592px) 100vw, 592px\" \/><\/p>\n<p>Neste trabalho, apresentamos um estudo do transporte el\u00e9trico, t\u00e9rmico e termoel\u00e9trico em bismuto elementar, que apresenta um coeficiente de Nernst muito maior do que o encontrado em metais correlacionados. N\u00f3s argumentamos que isso \u00e9 devido \u00e0 combina\u00e7\u00e3o de uma densidade de portadores excepcionalmente baixa com um livre caminho m\u00e9dio muito longo. Semimetais de el\u00e9trons pesados que mant\u00eam um comportamento met\u00e1lico na presen\u00e7a de um campo magn\u00e9tico, emergem como candidatos promissores para resfriamento termomagn\u00e9tico a baixas temperaturas.<\/p>\n<p>9)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-129 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A10-300x48.jpg\" alt=\"\" width=\"581\" height=\"93\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A10-300x48.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A10.jpg 662w\" sizes=\"auto, (max-width: 581px) 100vw, 581px\" \/><\/p>\n<p>Neste trabalho n\u00f3s demonstramos que os efeitos Hall qu\u00e2nticos inteiros e semi-inteiros reportados para grafenos de camada dupla e camada \u00fanica ocorrem simultaneamente em amostras de HOPG.<\/p>\n<p>10)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-131 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A11-300x80.jpg\" alt=\"\" width=\"603\" height=\"161\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A11-300x80.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A11-768x204.jpg 768w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A11.jpg 780w\" sizes=\"auto, (max-width: 603px) 100vw, 603px\" \/><\/p>\n<p>Neste trabalho n\u00f3s relatamos a primeira observa\u00e7\u00e3o direta dos f\u00e9rmions relativ\u00edsticos de Dirac com dispers\u00e3o linear perto da zona de Brillouin na extremidade H, que coexistem com quasipart\u00edculas que t\u00eam uma dispers\u00e3o parab\u00f3lica perto de outra zona de Brilloiun na extremidade K. Al\u00e9m disso, tamb\u00e9m relatamos um grande pacote de el\u00e9tron que atribu\u00edmos a estados localizados induzidos por defeito. Portanto, o grafite apresenta um sistema no qual os f\u00e9rmions sem masssa de Dirac, as quasipart\u00edculas com massa efetiva finita e estados com defeitos, contribuem para uma din\u00e2mica eletr\u00f4nica de baixa energia.<\/p>\n<p>11)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-133 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A12-300x49.jpg\" alt=\"\" width=\"625\" height=\"102\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A12-300x49.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A12.jpg 675w\" sizes=\"auto, (max-width: 625px) 100vw, 625px\" \/><\/p>\n<p>Neste trabalho reportamos a primeira evid\u00eancia experimental inequ\u00edvoca para a ocorr\u00eancia de f\u00e9rmions de Dirac no grafite. A identifica\u00e7\u00e3o dos f\u00e9rmions de Dirac tornou-se poss\u00edvel devido \u00e0 an\u00e1lise de frequ\u00eancia de fase das oscila\u00e7\u00f5es qu\u00e2nticas de Haas van Alphen e Shubnikov de Haas. A identifica\u00e7\u00e3o de f\u00e9rmions bidimensionais de Dirac em grafite, sem d\u00favida, faz deste sistema um laborat\u00f3rio natural de estado s\u00f3lido para testar previs\u00f5es de teorias relativ\u00edsticas de f\u00e9rmions Dirac (2 + 1)-dimensionais.<\/p>\n<p>12)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-136 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A13-300x82.jpg\" alt=\"\" width=\"578\" height=\"158\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A13-300x82.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A13.jpg 671w\" sizes=\"auto, (max-width: 578px) 100vw, 578px\" \/><\/p>\n<p>Neste trabalho realizamos medidas de magnetotransporte em amostras de grafite pirol\u00edtico altamente orientado, conhecido como HOPG e monocristais Kish. O conjunto dos resultados revelou a transi\u00e7\u00e3o metal-isolante induzida por campo magn\u00e9tico aplicado perpendicularmente aos planos basais do grafite e tamb\u00e9m o aparecimento do estado met\u00e1lico reentrante induzido pela quantiza\u00e7\u00e3o de Landau. Observamos pela primeira vez o efeito Hall qu\u00e2ntico em amostras altamente anisotr\u00f3picas de HOPG no regime de altos campos magn\u00e9ticos.\u00a0 Os resultados proveram evid\u00eancias de correla\u00e7\u00f5es supercondutoras no regime da quantiza\u00e7\u00e3o dos n\u00edveis de Landau.<\/p>\n<p>13)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-138 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A14-300x164.jpg\" alt=\"\" width=\"563\" height=\"308\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A14-300x164.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A14-768x419.jpg 768w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A14.jpg 912w\" sizes=\"auto, (max-width: 563px) 100vw, 563px\" \/><\/p>\n<p>Neste trabalho, realizamos medidas de resist\u00eancia no plano n\u00e3o-local em um supercondutor Bi<sub>2<\/sub>Sr<sub>2<\/sub>CaCuCu O<sub>8+<\/sub><sub>d<\/sub> de alta temperatura cr\u00edtica com campo magn\u00e9tico de at\u00e9 9T aplicado ao longo do eixo-c cristalogr\u00e1fico. Nossos resultados demonstram que existe uma rede de v\u00f3rtices r\u00edgida sobre uma ampla \u00e1rea do diagrama de fase H-T, bem acima do limite da transi\u00e7\u00e3o de primeira ordem. Os resultados tamb\u00e9m fornecem evid\u00eancias para a fus\u00e3o da rede de v\u00f3rtices e o desacoplamento do l\u00edquido de v\u00f3rtice ocorrendo bem acima da transi\u00e7\u00e3o de primeira ordem.<\/p>\n<p>14)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-141 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A15-300x74.jpg\" alt=\"\" width=\"560\" height=\"138\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A15-300x74.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A15.jpg 732w\" sizes=\"auto, (max-width: 560px) 100vw, 560px\" \/><\/p>\n<p>Neste trabalho relatamos a primeira observa\u00e7\u00e3o da distribui\u00e7\u00e3o de campo e o desancoramento da rede de linhas de fluxo no estado de v\u00f3rtices de um supercondutor tipo-II por resson\u00e2ncia de spin de el\u00e9trons de condu\u00e7\u00e3o (CESR). O CESR foi realizado em MgB<sub>2<\/sub> (T<sub>c<\/sub> @ 39 K) \u00e0 4.1 GHz (1455 Oe) e 9.5 GHz (3390 Oe). O campo de distribui\u00e7\u00e3o, n(H), e um desvio padr\u00e3o de 14 Oe (\u00e0 28 K\/4.1 GHz e \u00e0 7 K\/9.5 GHz) foram inferidas, respectivamente, da distor\u00e7\u00e3o e amplia\u00e7\u00e3o do CESR no estado de v\u00f3rtices. Para ambas as frequ\u00eancias, a temperatura de desancoramento foi determinada.<\/p>\n<p>15)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-144 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A16-300x133.jpg\" alt=\"\" width=\"644\" height=\"285\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A16-300x133.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A16.jpg 567w\" sizes=\"auto, (max-width: 644px) 100vw, 644px\" \/><\/p>\n<p>Neste trabalho estudamos a magnetiza\u00e7\u00e3o de v\u00e1rias amostras bem caracterizadas de grafite pirol\u00edtico altamente orientado-HOPG, grafite Kish e grafite natural para investigar o sinal semelhante ao sinal ferromagn\u00e9tico recentemente relatado e sua poss\u00edvel rela\u00e7\u00e3o com as impurezas ferromagn\u00e9ticas. Os resultados de magnetiza\u00e7\u00e3o obtidos para amostras de HOPG em campos aplicados paralelamente \u00e0s camadas de grafeno &#8211; para minimizar o &#8216;background&#8217; diamagn\u00e9tico do grafite &#8211; n\u00e3o mostram correla\u00e7\u00e3o com a concentra\u00e7\u00e3o de impurezas magn\u00e9ticas. Nossos resultados sugerem uma origem intr\u00ednseca para o ferromagmetismo encontrado em grafite e discutimos poss\u00edveis origens do sinal ferromagn\u00e9tico.<\/p>\n<p>16)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-147 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A17-300x68.jpg\" alt=\"\" width=\"613\" height=\"139\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A17-300x68.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A17-768x173.jpg 768w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A17-1024x231.jpg 1024w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A17.jpg 1134w\" sizes=\"auto, (max-width: 613px) 100vw, 613px\" \/><\/p>\n<p>Neste trabalho relatamos medidas de magnetiza\u00e7\u00e3o realizadas em comp\u00f3sitos grafite-enxofre que demonstram claro comportamento supercondutor abaixo da temperatura cr\u00edtica T<sub>c<\/sub> = 35 K. O efeito Meissner-Ochsenfeld, supercorrentes de blindagem e ciclos de histerese caracter\u00edsticos de supercondutores do tipo-II foram medidos. Os resultados indicam que a supercondutividade ocorre em uma pequena fra\u00e7\u00e3o de amostra, possivelmente relacionadas com a superf\u00edcie da amostra.<\/p>\n<p>17)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-150 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A18-300x153.jpg\" alt=\"\" width=\"615\" height=\"314\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A18-300x153.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A18-768x393.jpg 768w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A18.jpg 933w\" sizes=\"auto, (max-width: 615px) 100vw, 615px\" \/><\/p>\n<p>Neste trabalho mostramos uma transi\u00e7\u00e3o induzida por campo magn\u00e9tico do comportamento do tipo met\u00e1lico para semicondutor na resist\u00eancia do plano basal em grafite pirol\u00edtico altamente orientado para um campo H<sub>c<\/sub> de 1 kOe aplicado ao longo do eixo-c hexagonal. A an\u00e1lise dos dados revela uma grande semelhan\u00e7a entre essa transi\u00e7\u00e3o e aquela medida em supercondutores de filmes finos e MOSFETs de Si. No entanto, em contraste com esses materiais, a transi\u00e7\u00e3o em grafite \u00e9 observ\u00e1vel em temperaturas de quase duas ordens de magnitude maior.<\/p>\n<p>18)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-153 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A19-300x212.jpg\" alt=\"\" width=\"601\" height=\"425\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A19-300x212.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A19.jpg 529w\" sizes=\"auto, (max-width: 601px) 100vw, 601px\" \/><\/p>\n<p>Neste trabalho identificamos os ciclos de histerese ferromagn\u00e9tico e supercondutor em amostras de grafite pirol\u00edtico altamente orientado abaixo e acima da temperatura ambiente. N\u00f3s tamb\u00e9m descobrimos que ambos os comportamentos s\u00e3o muito sens\u00edveis \u00e0 temperatura de tratamento relativamente baixa em compara\u00e7\u00e3o ao tratamento t\u00e9rmico da temperatura de s\u00edntese da amostra. A poss\u00edvel contribui\u00e7\u00e3o de impurezas magn\u00e9ticas e porque isto n\u00e3o parece ser a raz\u00e3o para os fen\u00f4menos observados \u00e9 discutida.<\/p>\n<p>19)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-156 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A20-300x125.jpg\" alt=\"\" width=\"636\" height=\"265\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A20-300x125.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A20-768x320.jpg 768w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A20.jpg 797w\" sizes=\"auto, (max-width: 636px) 100vw, 636px\" \/><\/p>\n<p>Neste trabalho, reportamos medidas da resistividade do plano basal r<sub>a<\/sub> (T, H) realizada em grafite pirol\u00edtico altamente orientado, com campo magn\u00e9tico paralelo ao eixo-c no intervalo de temperatura de 2 \u00e0 300 K e campos magn\u00e9ticos at\u00e9 8 T. Estes resultados fornecem evid\u00eancias para a ocorr\u00eancia de instabilidades supercondutoras induzidas por campo e tamb\u00e9m sem campo aplicado. Al\u00e9m disso, as medidas de magnetiza\u00e7\u00e3o M (T, H) sugerem a ocorr\u00eancia de instabilidades superficiais do tipo-Fermi que competem com as correla\u00e7\u00f5es supercondutoras<strong>.<\/strong><\/p>\n<p>20)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-159 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A21-300x173.jpg\" alt=\"\" width=\"612\" height=\"353\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A21-300x173.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A21.jpg 519w\" sizes=\"auto, (max-width: 612px) 100vw, 612px\" \/><\/p>\n<p style=\"text-align: left\">Neste trabalho realizamos medidas de magnetiza\u00e7\u00e3o em um filme fino de ni\u00f3bio (Nb) que revelaram a exist\u00eancia de um &#8220;segundo pico de magnetiza\u00e7\u00e3o&#8221; (SPM) bem abaixo do limite superior do campo cr\u00edtico Hc<sub>2<\/sub>(T). Os resultados fornecem evid\u00eancias claras que o SPM se origina de uma instabilidade termomagn\u00e9tica. A similaridade dos ciclos de magnetiza\u00e7\u00e3o medidos em um cristal supercondutor de alta temperatura cr\u00edtica Bi<sub>2<\/sub>Sr<sub>2<\/sub>CaCu<sub>2<\/sub>O<sub>8<\/sub> com aqueles em Nb, bem como sua depend\u00eancia em rela\u00e7\u00e3o ao tamanho do cristal e tamb\u00e9m ao incremento de campo magn\u00e9tico indicam que um mecanismo comum \u00e9 respons\u00e1vel para o SPM nestes supercondutores.<\/p>\n<p>21)<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\" wp-image-161 aligncenter\" src=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A22-300x77.jpg\" alt=\"\" width=\"705\" height=\"181\" srcset=\"https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A22-300x77.jpg 300w, https:\/\/sites.ifi.unicamp.br\/lmd\/files\/2019\/08\/A22.jpg 738w\" sizes=\"auto, (max-width: 705px) 100vw, 705px\" \/><\/p>\n<p>Neste trabalho medimos a dissipa\u00e7\u00e3o de energia e a ancoragem da rede de linhas de fluxo de cristais supercondutores em fun\u00e7\u00e3o da temperatura, campo magn\u00e9tico e o \u00e2ngulo q\u00a0 entre o campo magn\u00e9tico e os planos de CuO<sub>2<\/sub>. Para o supercondutor Bi<sub>2<\/sub>Sr<sub>2<\/sub>CaCu<sub>2<\/sub>O<sub>8<\/sub> e o supercondutor (Y<sub>0.94<\/sub>Gd<sub>0.06<\/sub>) Ba<sub>2<\/sub>CU<sub>3<\/sub>O<sub>6.83<\/sub> deficiente em oxig\u00eanio e para q ~ 0, observamos uma an\u00f4mala desancoragem da rede de linhas de fluxo em T ~ 30 K. Essa anomalia n\u00e3o pode ser explicada por um mecanismo de desancoramento termicamente ativado e sugere a exist\u00eancia de uma transi\u00e7\u00e3o da rede de linhas de fluxo.<\/p>\n<p><strong><u>Abaixo segue todas as publica\u00e7\u00f5es do LMD desde sua forma\u00e7\u00e3o em 1987 (em ordem cronol\u00f3gica)<\/u><\/strong><\/p>\n<p>&nbsp;<\/p>\n<p>[1] <em>\u201cResistivity as a function of composition in the superconducting Nb-Pt A15 phase\u201d<\/em>, S. Moehlecke, H. A. Borges, C. Santos, A. R. Sweedler, Journal of Low Temperature Physics <strong>70<\/strong> (1988) 449-457.<\/p>\n<p>[2] <em>\u201cHomogeneity range of the superconducting Chevrel phase-SnMo<sub>6<\/sub>X\u201d<\/em>, I. Scarminio, S. Moehlecke, Physics Letters A <strong>134<\/strong> (1988) 75-76.<\/p>\n<p>[3] <em>\u201cEnhancement of the intergranular superconducting properties in Bi<sub>2<\/sub>Sr<sub>2<\/sub>CaCu<sub>2<\/sub>O<sub>8<\/sub> with Li addtitions\u201d<\/em>, S. Moehlecke, C. H. Westphal, M. S. Torikachvili, J. A. Davis, I. C. L. Torriani, Physica C <strong>211<\/strong> (1993) 113-120.<\/p>\n<p>[4] <em>\u201cAnomalous behavior of the flux line lattice of vibrating high-T<sub>c<\/sub> superconductors at 30K in magnetic-fields parallel to the CuO<sub>2<\/sub> planes\u201d<\/em>, Y. Kopelevich, A. Gupta, P. Esquinazi, Physical Review Letters <strong>70<\/strong> (1993), 666-669.<\/p>\n<p>[5] <em>\u201cVibrating reed studies of vortex pinning in hgh-temperature superconductors\u201d<\/em>, A. Gupta, Y. Kopelevich, P. Esquinazi, F. I. Schulz, H. F. Braun, Journal of Alloys and Compounds <strong>195<\/strong> (1993), 419-426.<\/p>\n<p>[6] <em>\u201cMagnetic-field, temperature, geometry, and angle-dependent studies of vortex pinning in vibrating high T<sub>c<\/sub> superconductor crystals\u201d<\/em>, A. Gupta, Y. Kopelevich, M. Ziese, P. Esquinazi, P. Fischer, F. I. Schulz, H. F. Braun, Physical Review B 48 (1993) 6359-6373.<\/p>\n<p>[7] <em>\u201cIndium tin oxide as an optical memory material\u201d<\/em>, M. C. de Andrade, S. Moehlecke, Applied Physics-Material Science &amp; Processing <strong>58<\/strong> (1994) 503-506.<\/p>\n<p>[8] <em>\u201cFlux-line lattice melting in Bi<sub>2<\/sub>Sr<sub>2<\/sub>Ca<sub>2<\/sub>Cu<sub>3<\/sub>O<sub>10<\/sub>\u201d<\/em>, Y. Kopelevich, S. Moehlecke, J. H. S. Torres, Physical Review <strong>B<\/strong> 49 (1994) 1495-1498.<\/p>\n<p>[9] <em>\u201cMagnetic-field dependent quantum flux-creep in Bi<sub>2<\/sub>Sr<sub>2<\/sub>Ca<sub>2<\/sub>Cu<sub>3<\/sub>O<sub>10<\/sub>\u201d<\/em>, S. Moehlecke, Y. Kopelevich, Physica C <strong>222<\/strong> (1994) 149-156.<\/p>\n<p>[10] <em>\u201cThermally actived depinning in superconducting YBa<sub>2<\/sub>Cu<sub>3<\/sub>O<sub>7<\/sub> \u2013 a quantitative comparison with the theory of flux diffusion\u201d<\/em>, M. Ziese, P. Esquinazi, Y. Kopelevich, A. B. Sherman, Physica C <strong>224<\/strong> (1994) 79-90.<\/p>\n<p>[11] \u201c<em>Negative magnetic restoring force of the flux-line-lattice in anisotropic high Tc superconductors in the thermally activated depinning regime\u201d<\/em>, A. Gupta, Y. Kopelevich, P. Esquinazi, M. Ziese, H. F. Braun, Physica C <strong>235<\/strong> (1994) 3235-3236.<\/p>\n<p>[12] <em>A possible vortex-decoupling transition in Bi<sub>2<\/sub>Sr<sub>2<\/sub>Ca<sub>2<\/sub>Cu<sub>3<\/sub>O<sub>10<\/sub>\u201d<\/em>, Y. Kopelevich, S. Moehlecke, V. V. Makarov, Physica C <strong>249<\/strong> (1995) 144-150.<\/p>\n<p>[13] <em>\u201cLong-time temperature drift in a commercial SQUID magnetometer\u201d<\/em>, Y. Kopelevich, S. Moehlecke, Physica C <strong>253<\/strong> (1995) 325-328.<\/p>\n<p>[14] <em>\u201cParamagnetic contribution to the reversible magnetization of Nb<sub>3<\/sub>Pt\u201d<\/em>, Y. Kopelevich, S. Moehlecke, Czechoslovak Journal of Physics <strong>46<\/strong> (1996) 873-874.<\/p>\n<p>[15] <em>\u201cH-T phase diagram of Nb-O solid solution\u201d<\/em>, S. Moehlecke, Y. Kopelevich, Czechoslovak Journal of Physics <strong>46<\/strong> (1996) 871-872.<\/p>\n<p>[16] <em>\u201cFrozen magnetization in Bi<sub>2<\/sub>Sr<sub>2<\/sub>Ca<sub>2<\/sub>Cu<sub>3<\/sub>O<sub>10<\/sub>\u201d<\/em>, V. V. Makarov, Y. Kopelevich, S. Moehlecke, Physica C <strong>264<\/strong> (1996) 213-219.<\/p>\n<p>[17] <em>\u201cVortex-glass-type transition in YBa<sub>2<\/sub>Cu<sub>3<\/sub>O<sub>7-<\/sub><\/em><em><sub>d<\/sub><\/em><em> ceramics\u201d<\/em>, V. V. Makarov, Y. Kopelevich, Physical Review B <strong>54<\/strong> (1996) 84-85.<\/p>\n<p>[18] <em>\u201cQuantum creep of Josephson intergrain vortices in Bi<sub>2<\/sub>Sr<sub>2<\/sub>Ca<sub>2<\/sub>Cu<sub>3<\/sub>O<sub>10<\/sub>\u201d<\/em>, S. Moehlecke, Y. Kopelevich, Journal of Low Temperature Physics <strong>106<\/strong> (1997) 207-212.<\/p>\n<p>[19] <em>\u201cDisorder induced asymmetric magnetization in Bi<sub>2<\/sub>Sr<sub>2<\/sub>Ca<sub>2<\/sub>Cu<sub>3<\/sub>O<sub>10<\/sub>\u201d<\/em>, Y. Kopelevich, V. V. Makarov, S. Moehlecke, Physica C <strong>277<\/strong> (1997) 225-232.<\/p>\n<p>[20] <em>\u201cNonlocal in-plane resistance in high Tc superconducting films in the vicinity of a Kosterlitz-Thouless-type transition\u201d<\/em>, Y. Kopelevich, F. Ciovacco, P. Esquinazi, H. F. Braun, Journal of Low Temperature Physics <strong>111<\/strong> (1998) 11-17.<\/p>\n<p>[21] <em>\u201cAvalanchelike magnetic relaxation in the peak-effect regime of a Nb-O solid solution\u201d<\/em>, Y. Kopelevich, S. Moehlecke, Physical Review B <strong>58<\/strong> (1998) 2834-2837.<\/p>\n<p>[22] <em>\u201cSecond magnetization peak at low fields due to thermomagnetic flux-jump instability\u201d<\/em>, Y. Kopelevich, P. Esquinazi, Journal of Low Temperature Physics <strong>113<\/strong> (1998) 1-9.<\/p>\n<p>[23] <em>\u201cMechanical and squid measurements on Nb thin films: learning from a convencional superconductor\u201d<\/em>, P. Esquinazi, R. Hohne, Y. Kopelevich, A. V. Pan, M. Ziese, Physics and Materials Science of Vortex States, Flux Pinning and Dynamics, edited by R. Kossowsky, S. Bose, V. Pan, Z. Durusoy, Nato Advanced Science Institutes Series, Series E, Applied Sciences vol. <strong>356 <\/strong>(1999) 149-172.<\/p>\n<p>[24] <em>\u201cComment on \u2018nonlocal in-plane resistance due to vortex-antivortex dynamics in high Tc superconducting films\u2019 Reply\u201d, <\/em>Y. Kopelevich, P. Esquinazi, Physical Review Letters <strong>82<\/strong> (1999) 673-673.<\/p>\n<p>[25] <em>\u201cThermomagnetic Flux-Jump Instabilities and Second Magnetization peak in Bi<sub>2<\/sub>Sr<sub>2<\/sub>CaCu<sub>2<\/sub>O<sub>8<\/sub>\u201d, <\/em>Y. Kopelevich, S. Moehlecke, J. H. S. Torres, R. Ricardo da Silva; Journal of Low Temperature Physics <strong>116<\/strong> (1999) 261-276.<\/p>\n<p>[26] <em>\u201cVortex avalanches in Nb Thin films: global and local magnetization measurements\u201d<\/em>, P. Esquinazi, A. Setzer, D. Fuchs, Y. Kopelevich, E. Zeldov, C. Assmann, Physical Review B <strong>60<\/strong> (1999) 12454-12461.<\/p>\n<p><em>\u00a0<\/em>[27] <em>\u201cLandau level quantization and possible superconducting instabilities in highly oriented pyrolytic graphite\u201d<\/em>, Y. Kopelevich, V. V. Lemanov, S. Moehlecke, J. H. S. Torres, Physics of the Solid State <strong>41<\/strong> (1999) 1959-1962.<\/p>\n<p>[28] <em>\u201cA silicon micromechanical galvanometric scanner\u201d<\/em>, L. O. S. Ferreira, S. Moehlecke; Sensors and Actuators A-Physical <strong>73<\/strong> (1999) 252-260.<\/p>\n<p>[29] <em>\u201cVortex lattice deppining vs. vortex lattice melting: a pinning-based explanation of the equilibrium magnetization jump\u201d<\/em>, Y. Kopelevich, P. Esquinazi, Solid State Communications <strong>114 <\/strong>(2000) 241-244.<\/p>\n<p>[30] <em>\u201cEffect of the sample geometry on the second magnetization peak in single crystalline Ba<sub>0.63<\/sub>K<sub>0.37<\/sub>BiO<sub>3<\/sub> thick film\u201d<\/em>, A. Y. Galkin, Y. Kopelevich, P. Esquinazi, A. Setzer, V. M. Pan, S. N. Barilo, Solid State Communications <strong>114<\/strong> (2000) 1-4.<\/p>\n<p>[31] <em>\u201cMagnetic-field-driven superconducting-insulator-type transition in graphite\u201d<\/em>, H. Kempa, Y. Kopelevich, F. Mrowka, A. Setzer, J. H. S. Torres, R. Hohne, P. Esquinazi, Solid State Communications <strong>115<\/strong> (2000) 539-542.<\/p>\n<p>[32]<em>\u201cFerromagnetic- and superconducting-like behavior of graphite\u201d<\/em>, Y. Kopelevich, P. Esquinazi, J. H. S. Torres, S. Moehlecke, Journal of Low Temperature Physics <strong>119<\/strong> (2000) 691-702.<\/p>\n<p>[33] <em>\u201cSuperconducting YBa<sub>2<\/sub>Cu<sub>3<\/sub>O<sub>7-<\/sub><\/em><em><sub>d<\/sub><\/em><em> films on SrTiO<sub>3<\/sub> by electrodeposition process\u201d<\/em>, A. J. S. Machado, S. Moehlecke, Y. Kopelevich, A. Robin, C. A. M. dos Santos, Physica C <strong>341<\/strong>, (2000) 2369-2370.<\/p>\n<p>[34] <em>\u201cPossible electrical-current driven superconductor-insulator transition\u201d<\/em>, C. A. M. dos Santos, Y. Kopelevich, S. Moehlecke, A. J. S. Machado, Physica C <strong>341<\/strong> (2000)\u00a0 1047-1048.<\/p>\n<p>[35]<em> \u201cStaircase-Type Magnetic-Field Dependence of the Activation Energy of Josephson Interlayer Vortices in Bi<sub>2<\/sub>Sr<sub>2<\/sub>CaCu<sub>2<\/sub>O<sub>8<\/sub>\u201d<\/em>, J. C. P. Campoy, Y. Kopelevich, S. Moehlecke, R. Ricardo da Silva; Physical Review B <strong>63 <\/strong>(2001) 52510.<\/p>\n<p><em>\u00a0<\/em>[36] \u201c<em>Nonresonant Microwave Absorption in Bi2212 Single Crystal: Second Peak and Microwave Power Dependence\u201d<\/em>, V. V. Srinivasu, Ken-Ich Itoh, A. Hashizume, V. Sreedevi, H. Kohmoto, T. Endo, R. Ricardo da Silva, Y. Kopelevich, S. Moehlecke, T. Masui, and K. Hayashi; Journal of Superconductivity: Incorporating Novel Magnetism <strong>14 <\/strong>(2001) 41-46.<\/p>\n<p>[37] <em>\u201cNonmonotonic temperature dependence of the thermal Hall angle of a YBa<sub>2<\/sub>Cu<sub>3<\/sub>O<sub>6.95<\/sub> single crystal\u201d<\/em>, R. Ocana, A. Taldenkov, P. Esquinazi, Y. Kopelevich, Journal of Low Temperature Physics <strong>123<\/strong> (2001) 181-196.<\/p>\n<p>[38]<em> \u201cAnisotropy in Bi2212 Single Crystals Studied by Non-Resonant Microwave Absorption: Hysteresis and Line Shapes\u201d<\/em>, V. V. Srinivasu, , V. Sreedevi , A. Hashizume, H. Kohmoto, S. Moehlecke, R. Ricardo da Silva, Y. Kopelevich, T. Endo; Physica C <strong>36<\/strong> (2001) 282-285.<\/p>\n<p><em>\u00a0<\/em>[39]<em> \u201cIndication of Superconductivity at 35K in Grafite-Sulfur Composites\u201d<\/em>, R. Ricardo da Silva, J. H. S. Torres, Y. Kopelevich; Physical Review Letters <strong>87<\/strong> (2001) 147001.<\/p>\n<p><em>\u00a0<\/em>[40]<em> \u201cEvidence for Internal Field in Grafite: a Conduction Electron-Spin Resonance Study\u201d<\/em>, M. S. Sercheli, Y. Kopelevich, <strong>R. Ricardo da Silva<\/strong>, J. H. S. Torres, C. Rettori; Solid State Communications <strong>121<\/strong> (2002) 579-583.<\/p>\n<p><em>\u00a0<\/em>[41] <em>\u201cThermomagnetic instability effects vs. vortex matter phase transitions in type-II superconductors\u201d<\/em>, Y. Kopelevich, P. Esquinazi, Solid State Communications <strong>122<\/strong> (2002) 33-36.<\/p>\n<p>[42]<em> \u201cHigh-Temperature Superconductivity in Graphite-Sulfur Composites: Theoretical Analysis\u201d<\/em>, D. S. Galv\u00e3o, B. Laks, R. R. da Silva, J. H. S. Torres e Y. Kopelevich; Material Research Society Symposium Proceedings, Vol. <strong>689<\/strong> (2002) p. E5.2.1.<\/p>\n<p><em>\u00a0<\/em>[43] <em>\u201cField-induced metal-insulator transition in the c-axis resistivity of graphite\u201d<\/em>, H. Kempa, P. Esquinazi, Y. Kopelevich, Physical Review B <strong>24<\/strong> (2002) 241101.<\/p>\n<p>[44] <em>\u201cFerromagnetism in oriented graphite samples\u201d<\/em>, P. Esquinazi, A. Setzer, R. Hohne, C. Semmelhack, Y. Kopelevich, D. Spemann, T. Butz, B. Kohlstrunk, M. Losche, Physical Review B <strong>66<\/strong> (2002) 024429.<\/p>\n<p><em>\u00a0<\/em>[45]<em> \u201cConduction Electron Spin Resonance Evidence for Internal Field in Graphite\u201d<\/em>, M. S. Sercheli, Y. Kopelevich, R. Ricardo da Silva, J. H. S. Torres, C. Rettori; Physica B <strong>320<\/strong> (2002) 413-415.<\/p>\n<p><em>\u00a0<\/em>[46] <em>\u201cField distribution and flux-line depinning in MgB<sub>2<\/sub>\u201d<\/em>, R. R. Urbano, P. G. Pagliuso, C. Rettori, Y. Kopelevich, N. O. Moreno, J. L. Sarrao, Physical Review Letters <strong>89<\/strong> (2002) 087602.<\/p>\n<p><em>\u00a0<\/em>[47] <em>\u201cInterlayer conduction band states in graphite-sulfur composites\u201d<\/em>, E. Z. Kurmaev, A. V. Galakhov, A. Moewes, S. Moehlecke, Y. Kopelevich, Physical Review B <strong>66<\/strong> (2002) 193402.<\/p>\n<p>[48]<em> \u201cVortex Lattice in Bi<sub>2<\/sub>Sr<sub>2<\/sub>CaCu<sub>2<\/sub>O<sub>8+<\/sub><\/em><em><sub>d<\/sub><\/em><em> Well Above the First-Order Phase-Transition Boundary\u201d<\/em>, J. H. S. Torres, R. Ricardo da Silva, S. Moehlecke, Y. Kopelevich; Solid State Communications <strong>125<\/strong> (2003) 11-16.<\/p>\n<p><em>\u00a0<\/em>[49] <em>\u201cAbsence of metal-insulator transition and coherent interlayer transport in oriented graphite in parallel magnetic fields\u201d<\/em>, H. Kempa, H. C. Semmelhack, P. Esquinazi, Y. Kopelevich, Solid State Communications <strong>125<\/strong> (2003) 1-5.<\/p>\n<p>[50]<em> \u201cMagnetism in Photopolymerized Fullerenes\u201d<\/em>, T. L. Makarova, K.-H. Han, P. Esquinazi, R. R. da Silva, Y. Kopelevich, I. B. Zakharova, B. Sundqvist; Carbon <strong>41<\/strong> (2003) 1575-1584.<\/p>\n<p><em>\u00a0<\/em>[51]<em> \u201cGraphite as a Highly Correlated Electron Liquid\u201d<\/em>, Y. Kopelevich, P. Esquinazi J. H. S. Torres, R. Ricardo da Silva, H. Kempa; Advances in Solid State Physics, vol. <strong>43<\/strong> (2003) 207-222.<\/p>\n<p><em>\u00a0<\/em>[52] <em>\u201cStructural studies of magnetic polymerized fullerene\u201d<\/em>, T. L. Makarova, B. Sundqvist, Y. Kopelevich, Synthetic Metals <strong>137<\/strong> (2003) 1335-1337.<\/p>\n<p>[53]<em> \u201cReentrant Metallic Behavior of Grafite in the Quantum Limit\u201d<\/em>, Y. Kopelevich, J. H. S. Torres, R. R. da Silva, F. Mrowka, H. Kempa,\u00a0 P. Esquinazi; Physical Review Letters <strong>90<\/strong> (2003) 156402.<\/p>\n<p>[54] <em>\u201cInhomogeneous superconductivity in Bi<sub>2<\/sub>Sr<sub>2<\/sub>Ca<sub>1-x<\/sub>Pr<sub>x<\/sub>Cu<sub>2<\/sub>O<sub>8+<\/sub><\/em><em><sub>d<\/sub><\/em><em>\u201d<\/em>, C. A. M. dos Santos, S. Moehlecke, Y. Kopelevich, A. J. S Machado, Phyica C <strong>390<\/strong> (2003) 21-26.<\/p>\n<p>[55]<em> \u201cLocal Ferromagnetism in Microporous Carbon with the Structural Regularity of Zeolite Y\u201d<\/em>, Y. Kopelevich, R. R. da Silva, J. H. S. Torres, A. Penicaud, T. Kyotani; Physical Review B <strong>68<\/strong> (2003) 92408.<\/p>\n<p><em>\u00a0<\/em>[56] <em>\u201cMagnetothermal conductivity of highly oriented pyrolytic graphite in the quantum limit\u201d<\/em>, R. Ocana, P. Esquinazi, H. Kempa, J. H. S. Torres, Y. Kopelevich, Physical Review B <strong>68<\/strong> (2003) 165408.<\/p>\n<p>[57] <em>\u201cLocal superconductivity and ferromagnetism interplay in graphite-sulfur composites\u201d<\/em>, S. Moehlecke, Y. Kopelevich, M. B. Maple, Brazilian Journal of Physics <strong>33<\/strong> (2003) 762-765.<\/p>\n<p>[58] <em>\u201cGraphite as a bose metal\u201d<\/em>, Y. Kopelevich, Brazilian Journal of Physics <strong>33<\/strong> (2003) 737-739.<\/p>\n<p>[59]<em> \u201cMetal-Insulator-Metal Transitions, Superconductivity and Magnetism in Graphite\u201d<\/em>, Y. Kopelevich, P. Esquinazi, J. H. S. Torres, R. R. da Silva, H. Kempa, F. Mrowka e R. Ocana; Studies of High Temperature Superconductors, vol <strong>45<\/strong>, Ed. por A.V. Narlivar, Nova Sci. Pub., New York (2003).<\/p>\n<p>[60] <em>\u201cTesting the magnetism of polymerized fullerene\u201d<\/em>, D. W. Boukhvalov, P. F. Karimov, E. Z. Kurmaev, T. Hamilton, A. Moewes, L. D. Finkelstein, M. I. Katsnelson, V. A. Davydov, A. V. Eakhmanina, T. L. Makarova, Y. Kopelevich, S. Chiuzbaian, M. Neumann, Physical Review B <strong>69<\/strong> (2004) 115425.<\/p>\n<p>[61] <em>\u201cInteraction between superconducting and ferromagnetic order parameters in graphite-sulfur composites\u201d<\/em>, S. Moehlecke, Y. Kopelevich, M. B. Maple, Physical Review B 69 (2004) 134519.<\/p>\n<p>[62]<em> \u201cVortex Lattice in Bi<sub>2<\/sub>Sr<sub>2<\/sub>CaCu<sub>2<\/sub>O<sub>8+<\/sub><\/em><em><sub>d<\/sub><\/em><em> Well Above the First-Order Phase-Transition Boundary\u201d<\/em>, J. H. S. Torres, R. R. da Silva, S. Moehlecke, Y. Kopelevich; Physica C <strong>408\u2013410<\/strong> (2004) 566-567.<\/p>\n<p><em>\u00a0<\/em>[63] <em>\u201cHigh-temperature local superconductivity in grafite and graphite\u2013sulfur composites\u201d<\/em>, Y. Kopelevich, R. R. da Silva, J. H. S. Torres, S. Moehlecke, M. B. Maple; Physica C <strong>408\u2013410<\/strong> (2004) 77-78.<\/p>\n<p><em>\u00a0<\/em>[64] <em>\u201cPhase analysis of quantum oscillations in graphite\u201d<\/em>, I. A. Luk\u2019yanchuk, Y. Kopelevich, Physical Review Letters <strong>93<\/strong> (2004) 166402.<\/p>\n<p>[65] <em>\u201cMagnetic carbon (Retraction of vol 413, pg 716, 2001)\u201d<\/em>, T. L. Makarova, B. Sundqvist, R. Hohne, P. Esquinazi, Y. Kopelevich, P. Scharff, V. A. Davydov, L. S. Kashevarova, A. V. Rakhmanina, Nature <strong>436<\/strong> (2005) 1200.<\/p>\n<p>[66]<em> \u201cUniversal magnetic-field-driven metal-insulator-metal transformations in graphite and bismuth\u201d<\/em>, Y. Kopelevich, J. C. Medina Pantoja, R. R. da Silva, and S. Moehlecke; Physical Review B <strong>73<\/strong> (2006)165128.<\/p>\n<p>[67]<em> \u201cMagnetic-field-driven quantum critical behavior in graphite and bismuth\u201d<\/em>, Y. Kopelevich, J. C. Medina Pantoja, R. R. da Silva, S. Moehlecke; Annals of Physics <strong>321 <\/strong>(2006) 1575-1587.<\/p>\n<p>[68]<em> \u201cAnomalous Hall effect in graphite\u201d<\/em>, Y. Kopelevich, J. C. Medina Pantoja, R. R. da Silva, F. Mrowka, P. Esquinazi; Physics Letters A <strong>355<\/strong> (2006) 233-236.<\/p>\n<p>[69] <em>\u201cFirst direct observation of Dirac fermions in graphite\u201d<\/em>, S. Y. Zhou, G. H. Gweon, J. Graf, A. V. Fedorov, C. D. Sparatu, R. D. Diehl, Y. Kopelevich, D. H. Lee, S. G. Louie, A. Lanzara, Nature Physics <strong>2<\/strong> (2006) 595-599.<\/p>\n<p>[70] <em>\u201cDirac and normal fermions in graphite and graphene: implications of the quantum hall effect\u201d<\/em>, I. A. Luk\u2019yanchuk, Y. Kopelevich, Physical Review Letters <strong>97<\/strong> (2006) 256801.<\/p>\n<p>[71]<em> \u201cFerromagnetic and Superconducting Instabilities in Graphite\u201d<\/em>, Y. Kopelevich, S. Moehlecke, and R. R. da Silva; Carbon Based Magnetism, T. Makarova and F. Palacio (Editors) (2006) 417 Elsevier.<\/p>\n<p>[72] <em>\u201cNernst effect in semimetals: The effective mass and the figure of merit\u201d<\/em>, K. Behnia, M. A. Measson, Y. Kopelevich, Physical Review Letters 98 (2007) 076603.<\/p>\n<p>[73] <em>Ferromagnetism and superconductivity in carbon-based systems\u201d<\/em>, Y. Kopelevich, P. Esquinazi, Journal of Low Temperature Physics <strong>146<\/strong> (2007) 629-639.<\/p>\n<p>[74] <em>\u201cOscillating Nernst-Ettingshausen effect in bismuth across the quantum limit\u201d<\/em>, K. Behnia, M. A. Measson, Y. Kopelevich, Physical Review Letters <strong>98<\/strong> (2007) 166602.<\/p>\n<p>[75]<em> \u201cCharge ordering in amorphous WO<sub>x<\/sub> films\u201d<\/em>, Y. Kopelevich, R. R. da Silva, A. Rougier, I. A. Luk\u2019yanchuk; Physics Letters A <strong>368<\/strong> (2007) 419-422.<\/p>\n<p>[76] <em>\u201cSignatures of electron fractionalization in ultraquantum bismuth\u201d<\/em>, K. Behnia, L. Balicas, Y. Kopelevich, Science <strong>317<\/strong> (2007) 1729-1731.<\/p>\n<p>[77] <em>\u201cGraphene physics in graphite\u201d<\/em>, Y. Kopelevich, P. Esquinazi, Advanced Materials <strong>19<\/strong> (2007) 4559-4563.<\/p>\n<p>[78]<em> \u201cCharge ordering in amorphous WO<sub>x<\/sub> films\u201d<\/em>, Y. Kopelevich, R. R. da Silva, A. Rougier, I. A. Luk\u2019yanchuk; Physica B <strong>403<\/strong> (2008) 1211.<\/p>\n<p>[79] <em>\u201cLandau levels in bulk graphite by Raman spectroscopy\u201d<\/em>, A. F. Garcia-Flores, H. Terashita, E. Granado, Y. Kopelevich, Physical Review B <strong>79<\/strong> (2009) 113105.<\/p>\n<p>[80] <em>\u201cDirac fermions in graphite: The state of art\u201d<\/em>, I. A. Luk\u2019yanchuk, Y. Kopelevich, M. El Marssi, Physica B <strong>404<\/strong> (2009) 404-406.<\/p>\n<p>[81] <em>\u201cSignatures of inhomogeneous electronic state in quantum limit in graphite\u201d<\/em>, Y. Kopelevich, R. R. da Silva; International Journal of Modern Physics B <strong>23<\/strong> (2009) 2723.<\/p>\n<p>[82] <em>\u201cMagnetization measurement of a possible high-temperature superconducting state in amorphous carbon doped with sulfur\u201d<\/em>, I. Felner, Y. Kopelevich, Physical Review B <strong>79<\/strong> (2009) 233409.<\/p>\n<p>[83] \u201c<em>Searching for fractional quantum Hall effect in graphite\u201d<\/em>, Y. Kopelevich, B. Raquet, M. Goiran, W. Escoffier, R. R. da Silva, J. C. Medina Pantoja, I. A. Luk\u2019yanchuk, A. Sinchenko, P. Monceau; Physical Review Letters <strong>103<\/strong> (2009) 116802.<\/p>\n<p>[84] <em>\u201cNernst effect and dimensionality in the quantum limit\u201d<\/em>, Z. W. Zhu, H. Yang, B. Fauque, Y. Kopelevich, K. Behnia, Nature Physics 6 (2010) 26-29.<\/p>\n<p>[85] <em>Comment on \u201cConsistent interpretation of the low-temperature magnetotransport in graphite using the Slonczewski-Weiss-McClure 3D band-structure calculations\u201d<\/em>, I. A. Luk\u2019yanchuk, Y. Kopelevich, Physical Review Letters <strong>104<\/strong> (2010) 119701.<\/p>\n<p>[86] &#8220;<em>Probing the electrical anisotropy of multilayer graphene on the Si face of 6H-SiC\u201d<\/em>, B. Jouault, B. Jabakhanji, N. Camara, W. Desrat, A. Tiberj, J. R. Huntzinger, C. Consejo, A. Caboni, P. Godignon, Y. Kopelevich, J. Camassel, Physical Review B <strong>82<\/strong> (2010) 085438.<\/p>\n<p>[87]<em>\u00a0 &#8220;<\/em><em>Negative c-axis magnetoresistance in graphite\u201d<\/em>, Y. Kopelevich, R. R. da Silva, J. C. M. Pantoja, A. M. Bratkovsky; Physics Letters A<strong> 374 <\/strong>(2010) 4629-4632.<\/p>\n<p>[88]<em> \u201cEffect of oxygen adsorption on magnetic properties of graphite\u201d<\/em>, D.W. Boukhvalov, S. Moehlecke, R. R. da Silva, and Y. Kopelevich; Physical Review B <strong>83 <\/strong>(2011) 233408.<\/p>\n<p>[89]<em> \u201cLocal and global superconductivity in bismuth\u201d<\/em>, L. A. Baring, R. R. da Silva, Y. Kopelevich; Low Temperature Physics <strong>37 <\/strong>(2011) 889.<\/p>\n<p>[90] <em>\u201cComplex mixed state of the Pauli-limited superconductor CeCoIn<sub>5<\/sub>\u201d<\/em>, X. Gratens, L. Mendon\u00e7a-Ferreira, Y. Kopelevich, N. F. Oliveira, R. R. Urbano, R. A. Ribeiro, R. Movshovich, J. L. Sarrao, J. D. Thompson, Z. Fisk, P. G. Pagliuso, Physical Review B 85 (2012) 054502.<\/p>\n<p>[91] <em>\u201cMagnetism, magnetoresistance, and Shubnikov-de Haas oscillations in Na-implanted highly oriented pyrolytic graphite\u201d<\/em>, R. F. Pires, P. Pureur, M. Behar, J. L. Pimentel, J. Schaf, Y. Kopelevich, Journal of Applied Physics 111 (2012) 093922.<\/p>\n<p>[92] <em>Comment on \u201cRevealing common artifacts due to ferromagnetic inclusions in highly oriented pyrolytic graphite\u201d by M. Sepion et al<\/em>, D. Spemann, M. Rothermel, P. Esquinazi, M. A. Ramos, Y. Kopelevich, H. Ohldag,\u00a0 Europhysics Letters <strong>98<\/strong> (2012) 57006.<\/p>\n<p>[93] <em>\u201c<\/em>Extraordinary<em> magnetoresistance in graphite: experimental evidence for the time-reversal symmetry breaking\u201d, <\/em>Y. Kopelevich, R. R. da Silva, B. C. Camargo, A. Alexandrov; Journal of Physics: Condensed Matter <strong>25<\/strong> (2013) 466004.<\/p>\n<p>[94] <em>\u201cTuning the transport properties of graphene films grown by CVD on SiC(0001): Effect of in situ hydrogenation and annealing\u201d<\/em>, B. Jabakhanji, A. Michon, C. Consejo, W. Desrat, M. Portail, A. Tiberj, M. Paillet, A. Zahab, F. Cheynis, F. Lafont, F. Schopfer, W. Poirier, F. Bertran, P. Le Fevre, A. Taleb-Ibrahimi, D. Kazazis, W. Escoffier, B. C. Camargo, Y. Kopelevich, L. Camassel, B. Jouault, Physical Review B <strong>89<\/strong> (2014) 085422.<\/p>\n<p>[95]<em> \u201cPossible superconductivity in multi-layer-graphene by aplication of a gate voltage\u201d, <\/em>A. Ballestar, P. Esquinazi,\u00a0 J. Barzola-Quiquia, S. Dusari, F. Bern , R. R. da Silva, Y. Kopelevich; Carbon <strong>72 <\/strong>(2014) 312.<\/p>\n<p>[96] <em>\u201cStrong piezoelectricity in single-layer graphene deposited on SiO<sub>2<\/sub> grating substrates\u201d<\/em>, G. D. Rodrigues, P. Zelenovskiy, K. Romanyuk, S. Luchkin, Y. Kopelevich, A. Kholkin, Nature Communications <strong>6 <\/strong>(2015) 7572.<\/p>\n<p>[97] <em>\u201cUnstable and elusive superconductors\u201d<\/em>, Y. Kopelevich, R. R. da Silva, B. C. Camargo, Physica C <strong>514<\/strong> (2015) 237-245.<\/p>\n<p>[98] <em>\u201cEffect of structural disorder on quantum oscillations in graphite\u201d<\/em>, B. C. Camargo, Y. Kopelevich, A. Usher, S. B. Hubbard, Applied Physics Letters <strong>108<\/strong> (2016) 031604.<\/p>\n<p>[99] <em>\u201cLow-temperature photoluminescence in self-assembled diphenylalanine microtubes\u201d<\/em>, T. Nikitin, S. Kopyl, V. Y. Shur, Y. Kopelevich, A. L. Kholkin, Physics Letters A <strong>380<\/strong> (2016) 1658-1662.<\/p>\n<p>[100] Reply on: <em>\u201cOn the nature of strong piezoelectricity in graphene on SiO<sub>2<\/sub>\u201d, <\/em>G. D. Rodrigues, P. Zelenovskiy, K. Romanyuk, S. Luchkin, Y. Kopelevich, A. Kholkin, Nature Communications <strong>7 <\/strong>(2016) 11571.<\/p>\n<p>[101] <em>\u201cMagneto-transport properties of As-Implanted highly oriented pyrolytic graphite\u201d<\/em>, R. F. de Jesus, B. C. Camargo, R. R. da Silva, Y. Kopelevich, M. Behar, M. A. Gusmao, P. Pureur, Physica B <strong>500<\/strong> (2016) 118-125.<\/p>\n<p>[102] <em>\u201cElectronic transport and Raman spectroscopy characterization in ion-implanted highly oriented pyrolytic graphite\u201d<\/em>, R. F. de Jesus, A. M. Turatti, B. C. Camargo, R. R. da Silva, Y. Kopelevich, M. Behar, N. M. Balzaretti, M. A. Gusmao, P. Pureur, Journal of Low Temperature Physics <strong>190<\/strong> (2018) 141-153.<\/p>\n<p>[103] <em>\u201cRipplocation in graphite nanoplatelets during sonication assisted liquid phase exfoliation<\/em>\u201d, A. V. Alaferdov, R. Savu, M. A. Canesqui, Y. Kopelevich, R. R. da Silva, N. N. Rozhkova, D. A. Pavlov, Yu. V. Usov, G. M. de Trindade, S. A. Moshkalev, Carbon <strong>129<\/strong> (2018) 826-829.<\/p>","protected":false},"excerpt":{"rendered":"<p>Destaques das Publica\u00e7\u00f5es Cient\u00edficas do LMD 1) Neste trabalho reportamos uma forte resposta piezoel\u00e9trica de grafeno de mono-camada depositado em em substratos de Si\/SiO2. Esta atividade piezoel\u00e9trica em camadas de grafeno foi atribu\u00edda as intera\u00e7\u00f5es qu\u00edmicas dos \u00e1tomos de grafeno com o oxig\u00eanio subjacente proveniente do substrato de SiO2. E a magnitude desta atividade \u00e9 &hellip; <\/p>\n<p><a class=\"more-link btn\" href=\"https:\/\/sites.ifi.unicamp.br\/lmd\/publicacoes\/\">Continue lendo<\/a><\/p>\n","protected":false},"author":7,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-33","page","type-page","status-publish","hentry","nodate","item-wrap"],"_links":{"self":[{"href":"https:\/\/sites.ifi.unicamp.br\/lmd\/wp-json\/wp\/v2\/pages\/33","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sites.ifi.unicamp.br\/lmd\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/sites.ifi.unicamp.br\/lmd\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/sites.ifi.unicamp.br\/lmd\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/sites.ifi.unicamp.br\/lmd\/wp-json\/wp\/v2\/comments?post=33"}],"version-history":[{"count":39,"href":"https:\/\/sites.ifi.unicamp.br\/lmd\/wp-json\/wp\/v2\/pages\/33\/revisions"}],"predecessor-version":[{"id":186,"href":"https:\/\/sites.ifi.unicamp.br\/lmd\/wp-json\/wp\/v2\/pages\/33\/revisions\/186"}],"wp:attachment":[{"href":"https:\/\/sites.ifi.unicamp.br\/lmd\/wp-json\/wp\/v2\/media?parent=33"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}