Progress of ultrahigh-Q optical nanocavities using a silicon photonic crystal

Abstract

Photonic crystal nanocavities with high quality factors (Q) have attracted quite a bit of attention from many researchers. Particularly, silicon high-Q nanocavities have increased the record for the highest Q for a photonic crystal cavity over these last 15 years. Currently, silicon nanocavities are studied in various areas for industrial applications. The current record for a Q exceeds 10 million and furthermore, an average value of 2 million has been recently achieved even in the nanocavities fabricated on a large diameter substrate using photolithography. Therefore, silicon nanocavities will be used in a wider range of fields. Here we describe the recent studies for these ultrahigh-Q silicon nanocavities.