Pressure Tuning of Competing Charged and Neutral Exciton States in Quasi-2D Semiconductor Structures
نویسندگان
چکیده
Photoluminescence studies of neutral and charged excitons in modulation doped GaAs/Al0.3Ga0.7As quantum wells are performed as functions of applied pressure, temperature, and excitation power and frequency. Varying both pressure and incident power allows sensitive selection of the different exciton transitions. The G±X crossover in the barriers at 7 to 9 kbar accelerates photo-pumping of electrons to the barriers. A semi-empirical kinetic model is able to account for the power and pressure dependencies of this process.
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