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Ordering effect of Coulomb interaction in ballistic double-ring systems

C. M. Canali·W. Stephan·L. Y. Gorelik·R. I. Shekhter·M. Jonson
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Abstract

We study a model of two concentric onedimensional rings with incommensurate areas $A_1$ and $A_2$, in a constant magnetic field. The two rings are coupled by a nonhomogeneous inter-ring tunneling amplitude, which makes the one-particle spectrum chaotic. For noninteracting particles the energy of the many-body ground state and the first excited state exhibit random fluctuations characterized by the Wigner-Dyson statistics. In contrast, we show that the electron-electron interaction orders the magnetic field dependence of these quantities, forcing them to become periodic functions, with period $ \propto 1/(A_1 + A_2)$. In such a strongly correlated system the only possible source of disorder comes from charge fluctuations, which can be controlled by a tunable inter-ring gate voltage.

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C. M. Canali, W. Stephan, L. Y. Gorelik, R. I. Shekhter, M. Jonson. 1997-11-05. Ordering effect of Coulomb interaction in ballistic double-ring systems. https://doi.org/10.1016/s0038-1098(97)00310-4

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