Photoluminescence properties of a quantum system consisting of different size GaAs quantum wells
نویسندگان
چکیده
Photoluminescence properties of a quantum system consisting of four different size GaAs quantum wells (Lz=15, 7, 4.5 and 3 nm) clad by 50 nm thick Al0.24Ga0.76As barriers have been investigated by steady-state and time-resolved (TR) photoluminescence (PL) experiments at 13-300 K. It is found that the low temperature PL emission energy distribution is not uniform over the four excitonic emission bands and different from that expected for thermalized carriers at higher temperatures above 260 K. TR-PL measurements indicate that the non-uniform PL intensity distribution observed at low temperatures is a result of non-uniform quantum capture processes of photoexcited carriers.
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