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Title: Novel optical probes of InGaN/GaN light-emitting diodes.


Abstract not provided.

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Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
OSTI Identifier:
Report Number(s):
DOE Contract Number:
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physica Status Solidi (c); Related Information: Proposed for publication in Physica Status Solidi (c).
Country of Publication:
United States

Citation Formats

Kaplar, Robert, Kurtz, Steven Ross, and Koleske, Daniel David. Novel optical probes of InGaN/GaN light-emitting diodes.. United States: N. p., 2004. Web.
Kaplar, Robert, Kurtz, Steven Ross, & Koleske, Daniel David. Novel optical probes of InGaN/GaN light-emitting diodes.. United States.
Kaplar, Robert, Kurtz, Steven Ross, and Koleske, Daniel David. 2004. "Novel optical probes of InGaN/GaN light-emitting diodes.". United States. doi:.
title = {Novel optical probes of InGaN/GaN light-emitting diodes.},
author = {Kaplar, Robert and Kurtz, Steven Ross and Koleske, Daniel David},
abstractNote = {Abstract not provided.},
doi = {},
journal = {Physica Status Solidi (c)},
number = ,
volume = ,
place = {United States},
year = 2004,
month =
  • InGaN-based light-emitting diodes (LEDs) with some specific designs on the quantum barrier layers by alternating InGaN barriers with GaN barriers are proposed and studied numerically. In the proposed structure, simulation results show that the carriers are widely dispersed in the multi-quantum well active region, and the radiative recombination rate is efficiently improved and the electron leakage is suppressed accordingly, due to the appropriate band engineering. The internal quantum efficiency and light-output power are thus markedly enhanced and the efficiency droop is smaller, compared to the original structures with GaN barriers or InGaN barriers. Moreover, the gradually decrease of indium compositionmore » in the alternating quantum barriers can further promote the LED performance because of the more uniform carrier distribution, which provides us a simple but highly effective approach for high-performance LED applications.« less
  • A broadband superluminescent light emitting diode with In{sub 0.2}Ga{sub 0.8}N/GaN multiple quantum wells (MQWs) active region is investigated. The investigation is based on a theoretical model which includes the calculation of electronic states of the structure, rate equations, and the spectral radiation power. Two rate equations corresponding to MQW active region and separate confinement heterostructures layer are solved self-consistently with no-k selection wavelength dependent gain and quasi-Fermi level functions. Our results show that the superluminescence started in a current of ∼120 mA (∼7.5 kA/Cm{sup 2}) at 300 K. The range of peak emission wavelengths for different currents is 423–426 nm and the emission bandwidthmore » is ∼5 nm in the superluminescence regime. A maximum light output power of 7.59 mW is obtained at 600 mA and the peak modal gain as a function of current indicates logarithmic behavior. Also, the comparison of our calculated results with published experimental data is shown to be in good agreement.« less
  • The current-voltage and brightness-voltage characteristics and the electroluminescence spectra of blue InGaN/GaN-based light-emitting diodes are studied to clarify the cause of the decrease in the emission efficiency at high current densities and high temperatures. It is found that the linear increase in the emission intensity with increasing injection current changes into a sublinear increase, resulting in a decrease in efficiency as the observed photon energy shifts from the mobility edge. The emission intensity decreases with increasing temperature when the photon energy approaches the mobility edge; this results in the reduction in efficiency on overheating. With increasing temperature, the peak ofmore » the electroluminescence spectrum shifts to lower photon energies because of the narrowing of the band gap. The results are interpreted taking into account the fact that the density-of-states tails in InGaN are filled not only via trapping of free charge carriers, but also via tunneling transitions into the tail states. The decrease in the emission efficiency at high currents is attributed to the suppression of tunneling injection and the enhancement of losses via the nonradiative recombination channel 'under' the quantum well.« less