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Title: Refractive index of erbium doped GaN thin films

Abstract

GaN is an excellent host for erbium (Er) to provide optical emission in the technologically important as well as eye-safe 1540 nm wavelength window. Er doped GaN (GaN:Er) epilayers were synthesized on c-plane sapphire substrates using metal organic chemical vapor deposition. By employing a pulsed growth scheme, the crystalline quality of GaN:Er epilayers was significantly improved over those obtained by conventional growth method of continuous flow of reaction precursors. X-ray diffraction rocking curve linewidths of less than 300 arc sec were achieved for the GaN (0002) diffraction peak, which is comparable to the typical results of undoped high quality GaN epilayers and represents a major improvement over previously reported results for GaN:Er. Spectroscopic ellipsometry was used to determine the refractive index of the GaN:Er epilayers in the 1540 nm wavelength window and a linear dependence on Er concentration was found. The observed refractive index increase with Er incorporation and the improved crystalline quality of the GaN:Er epilayers indicate that low loss GaN:Er optical waveguiding structures are feasible.

Authors:
; ; ; ;  [1];  [2]
  1. Department of Electrical and Computer Engineering, Texas Tech University, Lubbock, Texas 79409 (United States)
  2. Department of Electrical and Computer Engineering, Polytechnic Institute of New York University, Brooklyn, New York 11201 (United States)
Publication Date:
OSTI Identifier:
22310932
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CHEMICAL VAPOR DEPOSITION; DOPED MATERIALS; ELLIPSOMETRY; EMISSION; ERBIUM ADDITIONS; GALLIUM NITRIDES; LINE WIDTHS; LOSSES; NEUTRON DIFFRACTION; ORGANOMETALLIC COMPOUNDS; REFRACTIVE INDEX; SAPPHIRE; SUBSTRATES; THIN FILMS; WAVELENGTHS; X-RAY DIFFRACTION

Citation Formats

Alajlouni, S., Sun, Z. Y., Li, J., Lin, J. Y., Jiang, H. X., E-mail: hx.jiang@ttu.edu, and Zavada, J. M. Refractive index of erbium doped GaN thin films. United States: N. p., 2014. Web. doi:10.1063/1.4893992.
Alajlouni, S., Sun, Z. Y., Li, J., Lin, J. Y., Jiang, H. X., E-mail: hx.jiang@ttu.edu, & Zavada, J. M. Refractive index of erbium doped GaN thin films. United States. doi:10.1063/1.4893992.
Alajlouni, S., Sun, Z. Y., Li, J., Lin, J. Y., Jiang, H. X., E-mail: hx.jiang@ttu.edu, and Zavada, J. M. 2014. "Refractive index of erbium doped GaN thin films". United States. doi:10.1063/1.4893992.
@article{osti_22310932,
title = {Refractive index of erbium doped GaN thin films},
author = {Alajlouni, S. and Sun, Z. Y. and Li, J. and Lin, J. Y. and Jiang, H. X., E-mail: hx.jiang@ttu.edu and Zavada, J. M.},
abstractNote = {GaN is an excellent host for erbium (Er) to provide optical emission in the technologically important as well as eye-safe 1540 nm wavelength window. Er doped GaN (GaN:Er) epilayers were synthesized on c-plane sapphire substrates using metal organic chemical vapor deposition. By employing a pulsed growth scheme, the crystalline quality of GaN:Er epilayers was significantly improved over those obtained by conventional growth method of continuous flow of reaction precursors. X-ray diffraction rocking curve linewidths of less than 300 arc sec were achieved for the GaN (0002) diffraction peak, which is comparable to the typical results of undoped high quality GaN epilayers and represents a major improvement over previously reported results for GaN:Er. Spectroscopic ellipsometry was used to determine the refractive index of the GaN:Er epilayers in the 1540 nm wavelength window and a linear dependence on Er concentration was found. The observed refractive index increase with Er incorporation and the improved crystalline quality of the GaN:Er epilayers indicate that low loss GaN:Er optical waveguiding structures are feasible.},
doi = {10.1063/1.4893992},
journal = {Applied Physics Letters},
number = 8,
volume = 105,
place = {United States},
year = 2014,
month = 8
}
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