Gallium Phosphide Photonic Crystal Nanocavities in the Visible

TL;DR

This paper reports the fabrication and characterization of gallium phosphide photonic crystal nanocavities operating at visible wavelengths, demonstrating their potential for integrated optoelectronic applications and coupling with visible emitters.

Contribution

It introduces high-quality gallium phosphide nanocavities at visible wavelengths with specific resonant properties and potential applications in optoelectronics and quantum emitters.

Findings

Resonances at wavelengths as low as 645 nm at room temperature.

Quality factors between 500 and 1700 for the nanocavities.

Mode volumes of approximately 0.7(lambda/n)^3.

Abstract

Photonic crystal nanocavities at visible wavelengths are fabricated in a high refractive index (n>3.2) gallium phosphide membrane. The cavities are probed via a cross-polarized reflectivity measurement and show resonances at wavelengths as low as 645 nm at room temperature, with quality factors between 500 and 1700 for modes with volumes 0.7(lambda/n)^3. These structures could be employed for submicron scale optoelectronic devices in the visible, and for coupling to novel emitters with resonances in the visible such as nitrogen vacancy centers, and bio- and organic molecules.