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Title: Absorptive lasing mode suppression in ZnO nano- and microcavities

Abstract

We conclusively explain the different lasing mode energies in ZnO nano- and microcavities observed by us and reported in literature. The limited penetration depth of usually used excitation lasers results in an inhomogeneous spatial gain region depending on the structure size and geometry. Hence, weakly or even nonexcited areas remain present after excitation, where modes are instantaneously suppressed by excitonic absorption. We compare the effects for ZnO microwires, nanowires, and tetrapod-like structures at room temperature and demonstrate that the corresponding mode selective effect is most pronounced for whispering-gallery modes in microwires with a hexagonal cross section. Furthermore, the absorptive lasing mode suppression will be demonstrated by correlating the spot size of the excitation laser and the lasing mode characteristic of a single ZnO nanowire.

Authors:
; ; ; ;  [1]
  1. Universität Leipzig, Institut für Experimentelle Physik II, Linnéstraße 5, 04103 Leipzig (Germany)
Publication Date:
OSTI Identifier:
22594335
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ABSORPTION; COMPARATIVE EVALUATIONS; CROSS SECTIONS; EXCITATION; GEOMETRY; INHIBITION; LASERS; NANOWIRES; PENETRATION DEPTH; TEMPERATURE RANGE 0273-0400 K; ZINC OXIDES

Citation Formats

Wille, M., Michalsky, T., Krüger, E., Grundmann, M., and Schmidt-Grund, R. Absorptive lasing mode suppression in ZnO nano- and microcavities. United States: N. p., 2016. Web. doi:10.1063/1.4960660.
Wille, M., Michalsky, T., Krüger, E., Grundmann, M., & Schmidt-Grund, R. Absorptive lasing mode suppression in ZnO nano- and microcavities. United States. doi:10.1063/1.4960660.
Wille, M., Michalsky, T., Krüger, E., Grundmann, M., and Schmidt-Grund, R. 2016. "Absorptive lasing mode suppression in ZnO nano- and microcavities". United States. doi:10.1063/1.4960660.
@article{osti_22594335,
title = {Absorptive lasing mode suppression in ZnO nano- and microcavities},
author = {Wille, M. and Michalsky, T. and Krüger, E. and Grundmann, M. and Schmidt-Grund, R.},
abstractNote = {We conclusively explain the different lasing mode energies in ZnO nano- and microcavities observed by us and reported in literature. The limited penetration depth of usually used excitation lasers results in an inhomogeneous spatial gain region depending on the structure size and geometry. Hence, weakly or even nonexcited areas remain present after excitation, where modes are instantaneously suppressed by excitonic absorption. We compare the effects for ZnO microwires, nanowires, and tetrapod-like structures at room temperature and demonstrate that the corresponding mode selective effect is most pronounced for whispering-gallery modes in microwires with a hexagonal cross section. Furthermore, the absorptive lasing mode suppression will be demonstrated by correlating the spot size of the excitation laser and the lasing mode characteristic of a single ZnO nanowire.},
doi = {10.1063/1.4960660},
journal = {Applied Physics Letters},
number = 6,
volume = 109,
place = {United States},
year = 2016,
month = 8
}
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