Autor: |
Kudrawiec, R., Motyka, M., Misiewicz, J., Yuen, H. B., Bank, S. R., Wistey, M. A., Bae, H. P., Harris Jr., James S. |
Předmět: |
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Zdroj: |
Journal of Applied Physics; 9/15/2005, Vol. 98 Issue 6, p063527, 7p, 7 Graphs |
Abstrakt: |
We have investigated characteristics of photoluminescence (PL) spectra obtained from as-grown and annealed GaN0.027As0.863Sb0.11/GaAs single quantum wells (SQWs). For the as-grown SQW at low temperature (<150 K), a broadband emission at ∼0.9 eV has been observed in addition to the band-gap-related recombination at ∼0.95 eV. After annealing, this broad emission disappears and the band-gap-related PL peak blueshifts ∼55 meV. The Stokes shift for this peak is 11 meV at 10 K. Thus, the low-temperature PL peak is mainly associated with the recombination of localized excitons. A rise in temperature leads to a continuous change in this peak; the contribution associated with localized excitons decreases while the contribution associated with free-excitons increases. Above 150 K the line shape gradually loses the Gaussian profile and a high-energy tail appears due to a thermal band filling effect. In this temperature range (>150 K), the PL peak is attributed to free-carrier recombination. [ABSTRACT FROM AUTHOR] |
Databáze: |
Complementary Index |
Externí odkaz: |
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