Nonparabolic band effects in GaAs/AlxGa1−xAs quantum dots and ultrathin quantum wells
نویسندگان
چکیده
We have investigated the optical properties of unstrained GaAs/AlxGa1−xAs quantum dot/well systems with the aim of studying the influence of confinement on the effective exciton mass, as determined from the photoluminescence line shift in high magnetic fields 50 T . The effective exciton mass is found to be more than twice the value for bulk GaAs. We attribute this to an enhanced nonparabolicity in the GaAs conduction band at the nanoscale.
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