Dynamic modulation of photonic crystal nanocavities using gigahertz acoustic phonons
Nature Photonics. doi:10.1038/nphoton.2011.208
Authors: Daniel A. Fuhrmann, Susanna M. Thon, Hyochul Kim, Dirk Bouwmeester, Pierre M. Petroff, Achim Wixforth & Hubert J. Krenner
Abstract: Photonic crystal membranes provide a versatile planar platform for on-chip implementations of photonic quantum circuits1–3. One prominent quantum element is a coupled system consisting of a nanocavity and a single quantum dot4–7, which forms a fundamental building block for elaborate quantum information networks8–10 and a cavity quantum electrodynamic system controlled by single photons3. To date, no fast tuning mechanism is available to achieve control within the systemcoherence time. Here, we demonstrate dynamic tuning bymonochromatic coherent acoustic phonons formed by a surface acoustic wave with frequencies exceeding 1.7 GHz, one order of magnitude faster than alternative approaches5–7. We resolve a periodic modulation of the optical mode exceeding eight times its linewidth, preserving both the spatial mode profile and a high quality factor. Because photonic crystal membranes confine photonic and phononic excitations11,12, coupling optical to acoustic frequencies, our technique opens up the way to coherent acoustic control of optomechanical crystals.