Effect of temperature on the optical properties of GaAsSbN/GaAs single quantum wells grown by molecular-beam epitaxy

Abstract

GaAsSbN/GaAs strained-layer single quantum wells grown on a GaAs substrate by molecular-beam epitaxy with different N concentrations were studied using the photoluminescence ͑PL͒ technique in the temperature range from 9 to 296 K. A strong redshift in optical transition energies induced by a small increase in N concentration has been observed in the PL spectra. This effect can be explained by the interaction between a narrow resonant band formed by the N-localized states and the conduction band of the host semiconductor. Excitonic transitions in the quantum wells show a successive red/blue/redshift with increasing temperature in the 2-100 K range. The activation energies of nonradiative channels responsible for a strong thermal quenching are deduced from an Arrhenius plot of the integrated PL intensity.

Nitrogen incorporation and optical studies of GaAsSbN∕GaAs single quantum well heterostructures

“…This is also consistent with the smaller shift observed in the temperature dependence data. It is worth noting that the overall redshift from 10 to 300 K is in the range of 30-50 meV for N ജ 0.9%, considerably smaller than those reported in the literature on the GaAsSbN / GaAs QWs and epilayers 7,8,12,31 and comparable to some of the lowest values reported for GaAsN ͑Refs. 28 and 32͒ and InGaAsN ͑Refs.…”

“…The low temperature photoluminescence ͑PL͒ characteristics in this system are reported [7][8][9][10][11][12] to be dominated by localized excitons due to the N induced localized states and potential fluctuations. Different annealing techniques have been improvised by various groups [1][2][3][4][5][6][7][8][9][10][11][12][13] for the annihilation of N related states to improve the PL efficiency. Our recent work 9,13 indicates that in situ annealing in an As ambient is more effective in the reduction of the density of localized states and nonradiative recombination centers that are responsible for PL thermal quenching.…”

Лазерная генерация в микродисках с активной областью на основе решеточно-согласованных InP/AlInAs наноструктур

“…4. Для гетероструктур с низкой плотностью дефектов такая зависимость описывается феноменологическим выраже-нием [13]:…”

Annealing time on carrier dynamics of ZnTe nanoparticles embedded in a near ultraviolet-transparent glass

“…The temperatures obtained from the GAUSSIAN fit were T x = 105 K (QD 2 /QD 1 ) and T x 0 = 145 K (QD 2 /bulk-like NCs) at 0 h, T x = 102 K (QD 2 /QD 1 ) and T x 0 = 126 K (QD 2 /bulk-like NCs) at 6 h, and T x = 97 K (QD 2 /QD 1 ) and T x 0 = 120 K (QD 2 /bulk-like NCs) at 8 h. These are the temperatures required to liberate carriers trapped in shallow virtual levels (probably attributable to QD 1 and QD 2 surface defects, respectively) [30]. Thus, the activation energy E A and E A 0 of these virtual levels (QD 1 and QD 2 ) can be found using the expression: These activation energy levels (E A ) decay with increasing annealing time.…”

“…Standard procedures for sample preparation were adopted. The powders were first mixed and then fused at 1300°C for 30 …”