Different wavelength ranges' WGM lasing from a ZnO microrod/R6G:PMMA microcavity
1 Peter Grünberg Research Centre, Nanjing University of Posts and Telecommunications - Nanjing, 210096, China
2 State Key Laboratory of Bioelectronics, Southeast University - Nanjing, 210096, China
Received: 27 December 2014
Accepted: 17 June 2015
Dual-wavelength or multi-wavelength laser sources have potential application in many areas. The ZnO material is an important candidate for ultraviolet (UV) micro/nanolasers for integrated photonic systems. In this paper, the dual-wavelength whispering-gallery-mode (WGM) laser is fabricated by symmetrically coating Rhodamine 6G (R6G):PMMA on a ZnO microrod, and realizes the UV WGM lasing and orange WGM lasing under optical pumping condition. The performance of the UV and orange WGM lasing, including the lasing threshold, emission intensity and quality factors (Q) are discussed. The resonance mechanism of the dual-wavelength WGM lasing is analyzed in detail. The two-dimensional FDTD simulation on optical-field distribution also confirms the resonance mechanism. This work is important to the design of optically and electrically pumped dual- or multi-wavelength WGM lasers.
PACS: 73.61.Ga – II-VI semiconductors / 42.55.Sa – Microcavity and microdisk lasers / 78.45.+h – Stimulated emission
© EPLA, 2015