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arXiv · 1404.4367

Perfect Metal Phases of One-Dimensional and Anisotropic Higher-Dimensional Systems

Eugeniu Plamadeala·Michael Mulligan·Chetan Nayak
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Abstract

We show that a 1D quantum wire with $23$ channels of interacting fermions has a perfect metal phase in which all weak perturbations that could destabilize this phase are irrelevant. Consequently, weak disorder does not localize it, a weak periodic potential does not open a gap, and contact with a superconductor also fails to open a gap. Similar phases occur for $N \geq 24$ channels of fermions, except for $N=25$, and for $8k$ channels of interacting bosons, with $k\geq 3$. Arrays of perfect metallic wires form higher-dimensional fermionic or bosonic perfect metals, albeit highly-anisotropic ones.

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Eugeniu Plamadeala, Michael Mulligan, Chetan Nayak. 2014-04-16. Perfect Metal Phases of One-Dimensional and Anisotropic Higher-Dimensional Systems. https://doi.org/10.1103/physrevb.90.241101

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