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Auger Coefficient
The Experts below are selected from a list of 219 Experts worldwide ranked by ideXlab platform
Bernd Witzigmann – 1st expert on this subject based on the ideXlab platform

on the uncertainty of the Auger recombination Coefficient extracted from ingan gan light emitting diode efficiency droop measurements
Applied Physics Letters, 2015CoAuthors: Joachim Piprek, Friedhard Romer, Bernd WitzigmannAbstract:IIInitride lightemitting diodes (LEDs) suffer from a severe efficiency reduction with increasing injection current (droop). Auger recombination is often seen as primary cause of this droop phenomenon. The corresponding Auger recombination Coefficient C is typically obtained from efficiency measurements using mathematical models. However, C Coefficients reported for InGaN active layers vary over two orders of magnitude. We here investigate this uncertainty and apply successively more accurate models to the same efficiency measurement, thereby revealing the strong sensitivity of the Auger Coefficient to quantum well properties such as electronhole ratio, electric field, and hot carrier escape.

On the uncertainty of the Auger recombination Coefficient extracted from InGaN/GaN lightemitting diode efficiency droop measurements
Applied Physics Letters, 2015CoAuthors: Joachim Piprek, Friedhard Romer, Bernd WitzigmannAbstract:IIInitride lightemitting diodes (LEDs) suffer from a severe efficiency reduction with increasing injection current (droop). Auger recombination is often seen as primary cause of this droop phenomenon. The corresponding Auger recombination Coefficient C is typically obtained from efficiency measurements using mathematical models. However, C Coefficients reported for InGaN active layers vary over two orders of magnitude. We here investigate this uncertainty and apply successively more accurate models to the same efficiency measurement, thereby revealing the strong sensitivity of the Auger Coefficient to quantum well properties such as electronhole ratio, electric field, and hot carrier escape.

Auger recombination and carrier transport effects in IIInitride quantum well light emitting diodes
Proceedings of SPIE, 2013CoAuthors: Marcus Deppner, Friedhard Romer, Bernd WitzigmannAbstract:Gallium nitride based light emitting diodes (LEDs) have established as powerful devices, that are well suited for
general lighting. Despite the progress within the recent years the socalled “efficiency droop” is still a central
issue of nitridebased LED research. Up to now, no widely accepted explanation is available for the reduction of
the internal quantum efficiency with increasing injection current.
We report on a novel mechanism contributing to efficiency droop, that combines two of the previously reported
effects: Auger recombination and carrier leakage. A sophisticated Auger model, that takes account of the overlap
of the wave functions, is extended to model the energy transfer towards the third involved carrier. This carrier
is assumed to be expelled from the well and regenerated in the continuum carrier population, where it can
contribute to carrier leakage.
A physicsbased simulation of a quantum well LED employing a semiclassical approach has been carried out
to demonstrate the impact of this effect. Depending on the parametrization, the inclusion of Auger expulsion
reduces the Auger Coefficient up to 50% when compared to a standard Auger model, which could explain the
discrepancy between calculated and experimentally extracted Auger Coefficients.
Joachim Piprek – 2nd expert on this subject based on the ideXlab platform

on the uncertainty of the Auger recombination Coefficient extracted from ingan gan light emitting diode efficiency droop measurements
Applied Physics Letters, 2015CoAuthors: Joachim Piprek, Friedhard Romer, Bernd WitzigmannAbstract:IIInitride lightemitting diodes (LEDs) suffer from a severe efficiency reduction with increasing injection current (droop). Auger recombination is often seen as primary cause of this droop phenomenon. The corresponding Auger recombination Coefficient C is typically obtained from efficiency measurements using mathematical models. However, C Coefficients reported for InGaN active layers vary over two orders of magnitude. We here investigate this uncertainty and apply successively more accurate models to the same efficiency measurement, thereby revealing the strong sensitivity of the Auger Coefficient to quantum well properties such as electronhole ratio, electric field, and hot carrier escape.

On the uncertainty of the Auger recombination Coefficient extracted from InGaN/GaN lightemitting diode efficiency droop measurements
Applied Physics Letters, 2015CoAuthors: Joachim Piprek, Friedhard Romer, Bernd WitzigmannAbstract:IIInitride lightemitting diodes (LEDs) suffer from a severe efficiency reduction with increasing injection current (droop). Auger recombination is often seen as primary cause of this droop phenomenon. The corresponding Auger recombination Coefficient C is typically obtained from efficiency measurements using mathematical models. However, C Coefficients reported for InGaN active layers vary over two orders of magnitude. We here investigate this uncertainty and apply successively more accurate models to the same efficiency measurement, thereby revealing the strong sensitivity of the Auger Coefficient to quantum well properties such as electronhole ratio, electric field, and hot carrier escape.
Friedhard Romer – 3rd expert on this subject based on the ideXlab platform

on the uncertainty of the Auger recombination Coefficient extracted from ingan gan light emitting diode efficiency droop measurements
Applied Physics Letters, 2015CoAuthors: Joachim Piprek, Friedhard Romer, Bernd WitzigmannAbstract:IIInitride lightemitting diodes (LEDs) suffer from a severe efficiency reduction with increasing injection current (droop). Auger recombination is often seen as primary cause of this droop phenomenon. The corresponding Auger recombination Coefficient C is typically obtained from efficiency measurements using mathematical models. However, C Coefficients reported for InGaN active layers vary over two orders of magnitude. We here investigate this uncertainty and apply successively more accurate models to the same efficiency measurement, thereby revealing the strong sensitivity of the Auger Coefficient to quantum well properties such as electronhole ratio, electric field, and hot carrier escape.

On the uncertainty of the Auger recombination Coefficient extracted from InGaN/GaN lightemitting diode efficiency droop measurements
Applied Physics Letters, 2015CoAuthors: Joachim Piprek, Friedhard Romer, Bernd WitzigmannAbstract:IIInitride lightemitting diodes (LEDs) suffer from a severe efficiency reduction with increasing injection current (droop). Auger recombination is often seen as primary cause of this droop phenomenon. The corresponding Auger recombination Coefficient C is typically obtained from efficiency measurements using mathematical models. However, C Coefficients reported for InGaN active layers vary over two orders of magnitude. We here investigate this uncertainty and apply successively more accurate models to the same efficiency measurement, thereby revealing the strong sensitivity of the Auger Coefficient to quantum well properties such as electronhole ratio, electric field, and hot carrier escape.

Auger recombination and carrier transport effects in IIInitride quantum well light emitting diodes
Proceedings of SPIE, 2013CoAuthors: Marcus Deppner, Friedhard Romer, Bernd WitzigmannAbstract:Gallium nitride based light emitting diodes (LEDs) have established as powerful devices, that are well suited for
general lighting. Despite the progress within the recent years the socalled “efficiency droop” is still a central
issue of nitridebased LED research. Up to now, no widely accepted explanation is available for the reduction of
the internal quantum efficiency with increasing injection current.
We report on a novel mechanism contributing to efficiency droop, that combines two of the previously reported
effects: Auger recombination and carrier leakage. A sophisticated Auger model, that takes account of the overlap
of the wave functions, is extended to model the energy transfer towards the third involved carrier. This carrier
is assumed to be expelled from the well and regenerated in the continuum carrier population, where it can
contribute to carrier leakage.
A physicsbased simulation of a quantum well LED employing a semiclassical approach has been carried out
to demonstrate the impact of this effect. Depending on the parametrization, the inclusion of Auger expulsion
reduces the Auger Coefficient up to 50% when compared to a standard Auger model, which could explain the
discrepancy between calculated and experimentally extracted Auger Coefficients.