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Spin Degeneracy and Conductance Fluctuations in Open Quantum Dots

J. A. Folk·S. R. Patel·K. M. Birnbaum·C. M. Marcus·C. I. Duruoz·J. S. Harris Jr
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Abstract

The dependence of mesoscopic conductance fluctuations on parallel magnetic field is used as a probe of spin degeneracy in open GaAs quantum dots. The variance of fluctuations at high parallel field is reduced from the low-field variance (with broken time-reversal symmetry) by factors ranging from roughly two in a 1 square-micron dot at low temperature, to four or greater in 8 square-micron dots. The factor of two is expected for simple Zeeman splitting of spin degenerate channels. A possible explanation for the unexpected larger factors in terms of field-dependent spin orbit scattering is proposed.

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J. A. Folk, S. R. Patel, K. M. Birnbaum, C. M. Marcus, C. I. Duruoz, J. S. Harris Jr. 2000-11-08. Spin Degeneracy and Conductance Fluctuations in Open Quantum Dots. https://doi.org/10.1103/physrevlett.86.2102

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