High Quality factor photonic crystal nanobeam cavities

TL;DR

This paper presents the design, fabrication, and experimental validation of silicon photonic crystal nanobeam cavities achieving extremely high theoretical and measured Quality factors, advancing optical resonator technology.

Contribution

It introduces a novel cavity design with a five-hole tapered mirror and precise length control, resulting in record-high theoretical and experimental Quality factors.

Findings

Theoretical Q factors up to 14 million were achieved.

Experimental Q factor measured nearly 750,000.

Cavity size effects on mode frequency and Q were confirmed experimentally.

Abstract

We investigate the design, fabrication and experimental characterization of high Quality factor photonic crystal nanobeam cavities in silicon. Using a five-hole tapered 1D photonic crystal mirror and precise control of the cavity length, we designed cavities with theoretical Quality factors as high as 14 million. By detecting the cross-polarized resonantly scattered light from a normally incident laser beam, we measure a Quality factor of nearly 750,000. The effect of cavity size on mode frequency and Quality factor was simulated and then verified experimentally.