Patterned silicon substrates: a common platform for room temperature GaN and ZnO polariton lasers

TL;DR

This paper introduces a novel silicon-based platform for room-temperature polariton lasers using patterned substrates, enabling high-quality cavities and strong coupling in GaN and ZnO systems for integrated device development.

Contribution

It presents a new fabrication platform with patterned silicon substrates for room-temperature polariton lasers, allowing high-quality cavity formation and strong coupling in GaN and ZnO materials.

Findings

Achieved cavity Q-factors of several thousands.

Demonstrated strong-coupling and polariton lasing at room temperature.

Enabled stacking of crack-free AlN/AlGaN layers on patterned silicon.

Abstract

A new platform for fabricating polariton lasers operating at room temperature is introduced: nitride-based distributed Bragg reflectors epitaxially grown on patterned silicon substrates. The patterning allows for an enhanced strain relaxation thereby enabling to stack a large number of crack-free AlN/AlGaN pairs and achieve cavity quality factors of several thousands with a large spatial homogeneity. GaN and ZnO active regions are epitaxially grown thereon and the cavities are completed with top dielectric Bragg reflectors. The two structures display strong-coupling and polariton lasing at room temperature and constitute an intermediate step in the way towards integrated polariton devices.