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Unconventional phonon-mediated superconductivity in MgB_{2}

G. M. Zhao
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Abstract

We have evaluated the total carrier mass enhancement factor f_{t} for MgB_{2} from two independent experiments (specific heat and upper critical field). These experiments consistently show that f_{t} = 3.1\pm0.1. The unusually large f_{t} is incompatible with the measured reduced gap (2Δ(0)/k_{B}T_{c} = 4.1) and the total isotope-effect exponent (α= 0.28\pm0.04) within the conventional phonon-mediated model. We propose an unconventional phonon-mediated mechanism, which is able to quantitatively explain the values of T_{c}, f_{t}, α, and the reduced energy gap in a consistent way.

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G. M. Zhao. 2001-11-14. Unconventional phonon-mediated superconductivity in MgB_{2}. https://doi.org/10.1088/1367-2630%2F4%2F1%2F303

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