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Parabolic negative magnetoresistance in p-Ge/Ge1-xSix heterostructures

Yu. G. Arapov·G. I. Harus·O. A. Kuznetsov·V. N. Neverov·N. G. Shelushinina
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Abstract

Quantum corrections to the conductivity due to the weak localization (WL) and the disorder-modified electron-electron interaction (EEI) are investigated for the high-mobility multilayer p-Ge/Ge1-xSix heterostructures at T = (0.1 - 20.0)K in magnetic field B up to 1.5T. Negative magnetoresistance with logarithmic dependence on T and linear in B^2 is observed for B >= 0.1T. Such a behavior is attributed to the interplay of the classical cyclotron motion and the EEI effect. The Hartree part of the interaction constant is estimated (F_/sigma = 0.44) and the WL and EEI contributions to the total quantum correction /Delta /sigma at B = 0 are separated (/Delta /sigma_{WL} ~ 0.3/Delta /sigma; /Delta /sigma_{EEI} ~ 0.7/Delta /sigma).

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Yu. G. Arapov, G. I. Harus, O. A. Kuznetsov, V. N. Neverov, N. G. Shelushinina. 2002-03-21. Parabolic negative magnetoresistance in p-Ge/Ge1-xSix heterostructures. https://doi.org/10.1134/1.1187817

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