Low-threshold upconverted single-mode lasing from CdS hexagonal microcavities. (5th February 2021)

• Record Type: Journal Article
• Authors: Mi, Yang; Kong, Lei; Wu, Yaoyao; Shi, Jinchun; Luo, Sheng-Nian
• Is Part Of: Nanotechnology. Volume 32:Number 17(2021)
• Publication Date: 2021-02-05
• Subjects: upconversion micro/nanolasers -- whispering-gallery-mode -- two-photon absorption -- single-mode lasing -- CdS microplatelets; Nanotechnology -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Publications périodiques; Nanotechnologies; Periodicals; 620.5
• DOI: 10.1088/1361-6528/abde61
• Languages: English
• ISSNs: 0957-4484

Abstract

Abstract: Upconversion micro/nanolasers are promising in fundamental physics research and practical applications. However, due to the limitation of gain medium and cavity quality, such lasers still suffer from a high lasing threshold ( P th ). Herein, upconverted whispering-gallery-mode lasing by two-photon absorption is achieved from CdS microplatelets with single-mode emission and low threshold (∼1.2 mJ cm −2 ). The threshold is three times lower than the best reported value in previous CdS upconversion lasers. Moreover, wavelength-tunable upconverted single-mode lasing is demonstrated from 510.4 to 518.9 nm with narrow linewidths around 0.85 nm, which is further verified through numerical simulations. In addition, the size-dependent lasing behavior is realized from single-mode to multimode oscillation; the corresponding lasing threshold decreases with increasing cavity edge length ( L ), following a P th ∝ 1/ L 2 relationship. These results underscore the promise of CdS microplatelets for developing chip-level frequency upconversion lasers.