Converging lasing from floating GaN Penrose microcavity

¹ Peter Grünberg Research Centre, College of Telecommunications and Information Engineering, Nanjing University of Posts and Telecommunications - XinMoFan Road, No. 66, 210003, Nanjing, China
² School of Physics and Telecommunications Engineering, Zhoukou Normal University - 466001, Zhoukou, China

^(a) zhugangyi@njupt.edu.cn
^(b) wangyj@njupt.edu.cn

Received: 22 March 2019
Accepted: 11 July 2019

Abstract

A floating GaN Penrose microcavity is fabricated by standard micro-and-nano fabrication techniques. Ultraviolet whispering gallery mode and Fabry-Pérot (F-P) mode lasings are obtained under optical pumping conditions at room temperature. The lasing characteristics of the emission intensity, the threshold and the resonance mechanism are presented. It should be noted that the Fabry-Pérot mode lasing could be converged due to the focusing effect of half-ellipse shape mirrors. Analysis of the lasing mode number is also given to confirm the lasing resonance mechanism. A commercial two-dimensional finite difference time domain simulation software is used to study near-field distribution and far-field distribution of a Penrose microcavity, presenting the resonance mechanism of two types of lasing modes. It is significant for improving devices' coupling efficiency, as well as the high-density integrated optoelectronics system.