Low-threshold GaN thin-film random laser through the weak scattering feedback

Hai Zhu, Anqi Chen, Yanyan Wu, Xu Ji, Yiting He, Zhiren Qiu, Zikang Tang, Siu Fung Yu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

6 Citations (Scopus)

Abstract

� 2017 IOP Publishing Ltd. Room temperature random lasing is demonstrated from a GaN epitaxy film with defect pits that result from growth imperfection. The optical coherence feedback is attributed to the formation of closed-loop paths of light through the scattering effect of the defect pits, which can avoid the difficulty of fabricating an artificial cavity. The random lasing action was also investigated through near and far-field patterns that imaged onto the CCD camera. In addition, the angle distribution of the laser beam was illustrated by use of an angle-resolved spectrometer. The lasing threshold, based on the weak scattering diffusive mode of GaN, is about one order of magnitude lower than that strong scattering random laser (RL). Hence, the results in this paper represent a low-cost technique to realize GaN-based laser diodes without the fabrication difficulty of cavity facets that result from the hardness of the sapphire substrate.
Original languageEnglish
Article number045107
JournalJournal of Physics D: Applied Physics
Volume50
Issue number4
DOIs
Publication statusPublished - 2 Feb 2017

Keywords

  • diffusive mode
  • multiple scattering
  • random lasing
  • semiconductor

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Acoustics and Ultrasonics
  • Surfaces, Coatings and Films

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