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arXiv · 1509.07865

Composite fermions and the field-tuned superconductor-insulator transition

Michael Mulligan·S. Raghu
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Abstract

In several two-dimensional films that exhibit a magnetic field-tuned superconductor to insulator transition (SIT), stable metallic phases have been observed. Building on the `dirty boson' description of the SIT, we suggest that the metallic region is analogous to the composite Fermi liquid observed about half-filled Landau levels of the two-dimensional electron gas. The composite fermions here are mobile vortices attached to one flux quantum of an emergent gauge field. The composite vortex liquid is a 2D non-Fermi liquid metal, which we argue is stable to weak quenched disorder. We describe several experimental consequences of the emergent composite vortex liquid.

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Michael Mulligan, S. Raghu. 2015-09-25. Composite fermions and the field-tuned superconductor-insulator transition. https://doi.org/10.1103/physrevb.93.205116

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