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Topological quantization of current in quantum tunnel contacts

S. A. Bulgadaev
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Abstract

It is shown that an account of the Berry phase (a topological $θ$-term) together with a dissipative term in the effective action $S[ϕ]$ of the tunnel contacts induces a strong quantization of the tunnel current at low temperatures. This phenomenon like the Coulomb blockade reflects a discrete charge structure of the quantum shot noise and can ensure a quantization of the tunnel current without a capacitive charging energy $E_C$, when the latter is strongly suppressed by quantum fluctuations. Since a value of the $θ$-parameter is determined by the gate voltage, this effect allows to control a current through the contact. A possible physical application of this effect is proposed.

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S. A. Bulgadaev. 2006-06-14. Topological quantization of current in quantum tunnel contacts. https://arxiv.org/abs/cond-mat/0605360

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