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arXiv · cond-mat/9506059

Supercurrent States in 1D Finite-Size Rings

V. A. Kashurnikov·A. I. Podlivaev·N. V. Prokof'ev·B. V. Svistunov
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Abstract

We consider topological supercurrent excitations (SC) in 1D mesoscopic rings. Under certain conditions such excitations are well-defined except for (i) a tunneling between resonating states with clockwise and anti-clockwise currents, which may be characterized by the amplitude $Δ$, and (ii) a decay of SC assisted by phonons of the substrate, both effects being macroscopically small. Most attention is paid to the calculation of the macroscopic scaling of $Δ$ (the main superfluid characteristic of a mesoscopic system) under different conditions: a commensurate system, a system with single impurity, and a disordered system. The results are in a very good agreement with the exact-diagonalization spectra of the boson Hubbard models. Apart from really 1D electron wires we discuss two other important experimental systems: the 2D electron gas in the FQHE state and quasi-1D superconducting rings. We suggest some experimental setups for studying SC, e.g., via persistent current measurements, resonant electro-magnetic absorption or echo signals, and relaxation of the metastable current states.

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V. A. Kashurnikov, A. I. Podlivaev, N. V. Prokof'ev, B. V. Svistunov. 1995-06-14. Supercurrent States in 1D Finite-Size Rings. https://doi.org/10.1103/physrevb.53.13091

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