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Full counting statistics of a chaotic cavity with asymmetric leads

O. M. Bulashenko
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Abstract

We study the statistics of charge transport in a chaotic cavity attached to external reservoirs by two openings of different size which transmit non-equal number of quantum channels. An exact formula for the cumulant generating function has been derived by means of the Keldysh-Green function technique within the circuit theory of mesoscopic transport. The derived formula determines the full counting statistics of charge transport, i.e., the probability distribution and all-order cumulants of current noise. It is found that, for asymmetric cavities, in contrast to other mesoscopic systems, the third-order cumulant changes the sign at high biases. This effect is attributed to the skewness of the distribution of transmission eigenvalues with respect to forward/backward scattering. For a symmetric cavity we find that the third cumulant approaches a voltage-independent constant proportional to the temperature and the number of quantum channels in the leads.

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O. M. Bulashenko. 2005-09-05. Full counting statistics of a chaotic cavity with asymmetric leads. https://doi.org/10.1088/1742-5468%2F2005%2F08%2Fp08013

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