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Interacting particles at a metal-insulator transition

Cosima Schuster·Rudolf A. Roemer·Michael Schreiber
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Abstract

We study the influence of many-particle interaction in a system which, in the single particle case, exhibits a metal-insulator transition induced by a finite amount of onsite pontential fluctuations. Thereby, we consider the problem of interacting particles in the one-dimensional quasiperiodic Aubry-Andre chain. We employ the density-matrix renormalization scheme to investigate the finite particle density situation. In the case of incommensurate densities, the expected transition from the single-particle analysis is reproduced. Generally speaking, interaction does not alter the incommensurate transition. For commensurate densities, we map out the entire phase diagram and find that the transition into a metallic state occurs for attractive interactions and infinite small fluctuations -- in contrast to the case of incommensurate densities. Our results for commensurate densities also show agreement with a recent analytic renormalization group approach.

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Cosima Schuster, Rudolf A. Roemer, Michael Schreiber. 2002-03-18. Interacting particles at a metal-insulator transition. https://doi.org/10.1103/physrevb.65.115114

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