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Title: Demonstration of a III-nitride vertical-cavity surface-emitting laser with a III-nitride tunnel junction intracavity contact

Abstract

We report on a III-nitride vertical-cavity surface-emitting laser (VCSEL) with a III-nitride tunnel junction (TJ) intracavity contact. The violet nonpolar VCSEL employing the TJ is compared to an equivalent VCSEL with a tin-doped indium oxide (ITO) intracavity contact. The TJ VCSEL shows a threshold current density (J{sub th}) of ∼3.5 kA/cm{sup 2}, compared to the ITO VCSEL J{sub th} of 8 kA/cm{sup 2}. The differential efficiency of the TJ VCSEL is also observed to be significantly higher than that of the ITO VCSEL, reaching a peak power of ∼550 μW, compared to ∼80 μW for the ITO VCSEL. Both VCSELs display filamentary lasing in the current aperture, which we believe to be predominantly a result of local variations in contact resistance, which may induce local variations in refractive index and free carrier absorption. Beyond the analyses of the lasing characteristics, we discuss the molecular-beam epitaxy (MBE) regrowth of the TJ, as well as its unexpected performance based on band-diagram simulations. Furthermore, we investigate the intrinsic advantages of using a TJ intracavity contact in a VCSEL using a 1D mode profile analysis to approximate the threshold modal gain and general loss contributions in the TJ and ITO VCSEL.

Authors:
; ; ; ; ;  [1]; ;  [1];  [2]
  1. Materials Department, University of California, Santa Barbara, California 93106 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
22489184
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 107; Journal Issue: 9; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABSORPTION; CARRIERS; DOPED MATERIALS; ELECTRONIC STRUCTURE; INDIUM OXIDES; LASERS; MOLECULAR BEAM EPITAXY; PERFORMANCE; REFRACTIVE INDEX; SIMULATION; SUPERCONDUCTING JUNCTIONS; SURFACES; THRESHOLD CURRENT; TIN; TUNNEL EFFECT; TUNNEL JUNCTIONS

Citation Formats

Leonard, J. T., E-mail: jtleona01@gmail.com, Young, E. C., Yonkee, B. P., Cohen, D. A., Margalith, T., Speck, J. S., DenBaars, S. P., Nakamura, S., and Department of Electrical and Computer Engineering, University of California, Santa Barbara, California 93106. Demonstration of a III-nitride vertical-cavity surface-emitting laser with a III-nitride tunnel junction intracavity contact. United States: N. p., 2015. Web. doi:10.1063/1.4929944.
Leonard, J. T., E-mail: jtleona01@gmail.com, Young, E. C., Yonkee, B. P., Cohen, D. A., Margalith, T., Speck, J. S., DenBaars, S. P., Nakamura, S., & Department of Electrical and Computer Engineering, University of California, Santa Barbara, California 93106. Demonstration of a III-nitride vertical-cavity surface-emitting laser with a III-nitride tunnel junction intracavity contact. United States. doi:10.1063/1.4929944.
Leonard, J. T., E-mail: jtleona01@gmail.com, Young, E. C., Yonkee, B. P., Cohen, D. A., Margalith, T., Speck, J. S., DenBaars, S. P., Nakamura, S., and Department of Electrical and Computer Engineering, University of California, Santa Barbara, California 93106. Mon . "Demonstration of a III-nitride vertical-cavity surface-emitting laser with a III-nitride tunnel junction intracavity contact". United States. doi:10.1063/1.4929944.
@article{osti_22489184,
title = {Demonstration of a III-nitride vertical-cavity surface-emitting laser with a III-nitride tunnel junction intracavity contact},
author = {Leonard, J. T., E-mail: jtleona01@gmail.com and Young, E. C. and Yonkee, B. P. and Cohen, D. A. and Margalith, T. and Speck, J. S. and DenBaars, S. P. and Nakamura, S. and Department of Electrical and Computer Engineering, University of California, Santa Barbara, California 93106},
abstractNote = {We report on a III-nitride vertical-cavity surface-emitting laser (VCSEL) with a III-nitride tunnel junction (TJ) intracavity contact. The violet nonpolar VCSEL employing the TJ is compared to an equivalent VCSEL with a tin-doped indium oxide (ITO) intracavity contact. The TJ VCSEL shows a threshold current density (J{sub th}) of ∼3.5 kA/cm{sup 2}, compared to the ITO VCSEL J{sub th} of 8 kA/cm{sup 2}. The differential efficiency of the TJ VCSEL is also observed to be significantly higher than that of the ITO VCSEL, reaching a peak power of ∼550 μW, compared to ∼80 μW for the ITO VCSEL. Both VCSELs display filamentary lasing in the current aperture, which we believe to be predominantly a result of local variations in contact resistance, which may induce local variations in refractive index and free carrier absorption. Beyond the analyses of the lasing characteristics, we discuss the molecular-beam epitaxy (MBE) regrowth of the TJ, as well as its unexpected performance based on band-diagram simulations. Furthermore, we investigate the intrinsic advantages of using a TJ intracavity contact in a VCSEL using a 1D mode profile analysis to approximate the threshold modal gain and general loss contributions in the TJ and ITO VCSEL.},
doi = {10.1063/1.4929944},
journal = {Applied Physics Letters},
number = 9,
volume = 107,
place = {United States},
year = {Mon Aug 31 00:00:00 EDT 2015},
month = {Mon Aug 31 00:00:00 EDT 2015}
}
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