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Driving a Superconductor to Insulator Transition with Random Gauge Fields.

ABSTRACT: Typically the disorder that alters the interference of particle waves to produce Anderson localization is potential scattering from randomly placed impurities. Here we show that disorder in the form of random gauge fields that act directly on particle phases can also drive localization. We present evidence of a superfluid bose glass to insulator transition at a critical level of this gauge field disorder in a nano-patterned array of amorphous Bi islands. This transition shows signs of metallic transport near the critical point characterized by a resistance , indicative of a quantum phase transition. The critical disorder depends on interisland coupling in agreement with recent Quantum Monte Carlo simulations. We discuss how this disorder tuned SIT differs from the common frustration tuned SIT that also occurs in magnetic fields. Its discovery enables new high fidelity comparisons between theoretical and experimental studies of disorder effects on quantum critical systems.

SUBMITTER: Nguyen HQ

PROVIDER: S-EPMC5128869 | biostudies-other | 2016 Nov

REPOSITORIES: biostudies-other

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Driving a Superconductor to Insulator Transition with Random Gauge Fields.

Nguyen H Q HQ Hollen S M SM Shainline J J Xu J M JM Valles J M JM

Scientific reports 20161130

Typically the disorder that alters the interference of particle waves to produce Anderson localization is potential scattering from randomly placed impurities. Here we show that disorder in the form of random gauge fields that act directly on particle phases can also drive localization. We present evidence of a superfluid bose glass to insulator transition at a critical level of this gauge field disorder in a nano-patterned array of amorphous Bi islands. This transition shows signs of metallic t ...[more]

PMID: 27901081

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