Degeneracy and effective mass in the valence band of two-dimensional (100)-GaAs quantum well systems

作者：Tarquini Vinicio^*; Knighton Talbot; Wu Zhe; Huang Jian; Pfeiffer Loren; West Ken

来源：Applied Physics Letters, 2014, 104(9): 092102.

DOI：10.1063/1.4867086

Quantum Hall measurement of two-dimensional high-mobility [mu similar to 2 x 10(6) cm(2)/(V . s)] hole systems confined in a 20 nm wide (100)-GaAs quantum well have been performed for charge densities between 4 and 5 x 10(10) cm(-2) in a temperature range of 10-160 mK. The Fourier analysis of the Shubnikov-de Haas (SdH) oscillations of the magnetoresistance vs. the inverse of the magnetic field 1/B reveals a single peak, indicating a degenerate heavy hole (HH) band. The hole density p = (e/h) . f agrees with the Hall measurement result within 3%. The HH band degeneracy is understood through the diminishing spin-orbit interaction due to the low charge density and the nearly symmetric confinement. SdH oscillations fitted for 0.08 T <= B <= 0.24 T to the Dingle parameters yield an effective mass between 0.30 and 0.50 m(e) in good agreement with previous cyclotron resonance results.

• 出版日期2014-3-3