Excitation dependent photoluminescence measurements of the nonradiative lifetime and quantum efficiency in GaAs

Abstract

Articles you may be interested inStrong excitation intensity dependence of the photoluminescence line shape in GaAs1−xBix single quantum well samples J. Appl. Phys. 113, 144308 (2013) The nonradiative lifetime and spontaneous emission quantum efficiency in molecular-beam epitaxy grown bulk GaAs is determined using injection level dependent photoluminescence ͑PL͒ measurements. These measurements were performed at temperatures of 300, 230, 100, and 50 K using a HeNe pump laser with powers ranging from 0.3 to 40 mW. The quantum efficiency and lifetime is inferred from the power law relation linking pump power and integrated PL signal that is predicted by the rate equations. The nonradiative lifetime for bulk GaAs is determined to be 0.3 s, with an additional temperature dependent component attributed to the AlGaAs barriers that rapidly reduces the nonradiative lifetime at temperatures above 230 K. The peak quantum efficiency is Ͼ0.96 at 300 K and Ͼ0.99 at temperatures below 230 K.

Observation of suppressed Auger mechanism in type-I quantum well structures with delocalized electron-hole wavefunctions

“…[20][21][22] The calculation of B is in close agreement with the average experimental values, confirming that the analytical evaluation is robust and valid as reported by Ref. 18. The Extracted Auger recombination rates versus temperature are shown in Fig.…”

“…This technique is based on the carrier density dependency of the non-radiative and radiative recombination mechanisms. 18 A laser diode with a wavelength of 980 nm (Agilent FPL4916-240) was used for pumping the material. The laser was current-modulated with a duty cycle of 1% to avoid heating the sample and reducing the accuracy of the measurement.…”

The Influence of Doping on the Optoelectronic Properties of PbS Colloidal Quantum Dot Solids

“…1(a). The variation of the excitonic band-edge emission with photoexcitation density is characteristic of colloidal QDs, exhibiting an approximately monomolecular regime at low photoexcitation densities, followed by a sublinear dependence with slopes of ~0.7 as Auger recombination becomes the dominant recombination channel (expected Auger slope of 0.67 27 ). It is noted that both of the two Gaussian-resolved spectral components of the undoped QD films exhibit identical excitation behavior leaving the PL lineshape of the undoped QDs unaffected by the excitation power.…”

A semi-analytical model for semiconductor solar cells

“…(19) and (20), with the junction thickness, d, explicitly shown. Upon substituting the analytical expression for B, 24 and using c e;upper ¼ e upper =ð4a g d Á n 2 g Þ and c e;lower ¼ e lower =ð4a g dÞ, Eq. (9) is obtained, where a g is the absorption coefficient at the average photon energy of the spontaneous emission spectrum.…”