Suspended single mode microdisk lasers

TL;DR

This paper presents a novel method for achieving single mode lasing in subwavelength suspended microdisk resonators by using bridges to control wave confinement and mode quality, enabling preselected mode operation at telecommunication wavelengths.

Contribution

It introduces a simple bridge-based technique to enhance mode selectivity and quality factor in microdisk lasers, facilitating single mode lasing at desired wavelengths.

Findings

Achieved single mode lasing in microdisks at telecommunication wavelengths.

Demonstrated control of mode confinement using bridge symmetry and number.

Improved quality factor of microdisks with bridge structures.

Abstract

Miniature semiconductor lasers have attracted a large amount of interest owing to their potential as highly integrated components in photonic circuits or in sensors. Particularly, microdisk lasers exploiting whispering gallery modes have been regarded as an important candidate because of their relatively small footprint and low threshold. However, it has been challenging for microdisk to operate under single mode operation and to lase in a preselected mode. We report subwavelength microdisk resonators suspended in air with connecting bridges and propose a simple method using the number and symmetry of bridges to enhance or reduce wave confinement in the whispering gallery cavity. Moreover, a suitable choice of bridges increases the quality factor of microdisks compared to microdisks resonator without bridges. Using this method, we demonstrate single mode lasing of preselected modes at telecommunication wavelength.