H1 photonic crystal cavitites for hybrid quantum information protocols

TL;DR

This paper presents optimized H1 photonic crystal cavities with high light radiation efficiency and fiber coupling, suitable for hybrid quantum information protocols involving local qubits and photons.

Contribution

It introduces a novel design of H1 photonic crystal cavities with enhanced far-field emission and coupling efficiency, validated through numerical and experimental methods.

Findings

80% of light radiated within NA 0.8

92% coupling efficiency to single-mode fiber

Resonant reflection spectroscopy shows >50% cavity mode visibility

Abstract

Hybrid quantum information protocols are based on local qubits, such as trapped atoms, NV centers, and quantum dots, coupled to photons. The coupling is achieved through optical cavities. Here we demonstrate far-field optimized H1 photonic crystal membrane cavities combined with an additional back reflection mirror below the membrane that meet the optical requirements for implementing hybrid quantum information protocols. Using numerical optimization we find that 80% of the light can be radiated within an objective numerical aperture of 0.8, and the coupling to a single-mode fiber can be as high as 92%. We experimentally prove the unique external mode matching properties by resonant reflection spectroscopy with a cavity mode visibility above 50%.