Single-Mode Emission in InP Microdisks on Si using Au Antenna

TL;DR

This paper demonstrates that Au nanorod antennas on InP microdisks can suppress multimode lasing and achieve stable single-mode emission across a broad temperature range, enhancing on-chip photonic device performance.

Contribution

It introduces a method to control mode emission in InP microdisk lasers on Si using Au antennas, enabling stable single-mode operation over wide temperature ranges.

Findings

Au antennas suppress side modes in InP microdisk lasers.

Single mode emission is stable from 200 K to 300 K.

Antenna size and placement influence emission patterns.

Abstract

An important building block for on-chip photonic applications is a scaled emitter. Whispering gallery mode cavities based on III-Vs on Si allow for small device footprints and lasing with low thresholds. However, multimodal emission and wavelength stability over a wider range of temperature can be challenging. Here, we explore the use of Au nanorods on InP whispering gallery mode lasers on Si for single mode emission. We show that by proper choice of the antenna size and positioning, we can suppress the side-modes of a cavity and achieve single mode emission over a wide excitation range. We establish emission trends by varying the size of the antenna and show that the far-field radiation pattern differs significantly for devices with and without antenna. Furthermore, the antenna-induced single mode emission is dominant from room temperature (300 K) down to 200 K, whereas the cavity without an antenna is multimodal and its dominant emission wavelength is highly temperature dependent.