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Anomalous Carrier Lifetime Enhancement and Effective Mass Discontinuity Observed during Magnetic-field-induced Subband Depopulation in a Parabolic Quantum Well

G. R. Facer·B. E. Kane·R. G. Clark·L. N. Pfeiffer
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Abstract

In GaAs/AlGaAs parabolic quantum wells, subbands are depopulated by a magnetic field in the well plane. A small additional perpendicular field induces Shubnikov-de-Haas (SdH) oscillations which we have used to determine the carrier density, effective mass, and lifetime, thoughout the two subband to one subband transition. The masses of carriers in the first and second subbands differ by 50% near the threshold of population of the second subband. The second subband SdH lifetime is enhanced near the threshold, even though the onset of two subband transport increases the sample resistance.

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G. R. Facer, B. E. Kane, R. G. Clark, L. N. Pfeiffer. 1997-07-08. Anomalous Carrier Lifetime Enhancement and Effective Mass Discontinuity Observed during Magnetic-field-induced Subband Depopulation in a Parabolic Quantum Well. https://doi.org/10.1016/s0921-4526(98)00351-2

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