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Shot-Noise Signatures of 0.7 Structure and Spin in a Quantum Point Contact

L. DiCarlo·Y. Zhang·D. T. McClure·D. J. Reilly·C. M. Marcus·L. N. Pfeiffer·K. W. West
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Abstract

We report simultaneous measurement of shot noise and dc transport in a quantum point contact as a function of source-drain bias, gate voltage, and in-plane magnetic field. Shot noise at zero field exhibits an asymmetry related to the 0.7 structure in conductance. The asymmetry in noise evolves smoothly into the symmetric signature of spin-resolved electron transmission at high field. Comparison to a phenomenological model with density-dependent level splitting yields good quantitative agreement.

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L. DiCarlo, Y. Zhang, D. T. McClure, D. J. Reilly, C. M. Marcus, L. N. Pfeiffer, K. W. West. 2006-06-09. Shot-Noise Signatures of 0.7 Structure and Spin in a Quantum Point Contact. https://doi.org/10.1103/physrevlett.97.036810

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