High-Q/V photonic crystal cavities realized by an effective Aubry-Andre-Harper bichromatic potential

Galli, M;Simbula, A

Second

;Shatzl, M;Zagaglia, L;Alpeggiani, F;Shaffler, F;Fromherz, T;Gerace, D

2017-01-01

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Abstract

We report on the realization of high-Q/V silicon photonic crystal cavities with resonance wavelengths in the telecom window around 1.55 mu m. The cavity designs are based on an effective Aubry-Andre-Harper bichromatic potential, defined by the superposition of two one-dimensional lattices with an incommensurate ratio between their periodicity constants. This peculiar confinement mechanism allows to achieve an ultra-high-Q factor and diffraction-limited mode volume. Several photonic crystal nanocavities in a silicon membrane geometry have been realized with measured Q-factors in the one million range, as determined by resonant scattering experiments. The generality of the proposed designs and their easy implementation and scalability make these results particularly interesting for realizing highly performing photonic nanocavities on different material platforms and operational wavelengths.