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arXiv · 1205.5746

Strong-Coupling Superconductivity with Mixed Even- and Odd-Frequency Pairing

Hiroaki Kusunose·Masashige Matsumoto·Mikito Koga
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Abstract

We investigate general structure of Landau free energy for stabilizing a novel superconducting state with both even-frequency and odd-frequency components in gap function. On the basis of the Luttinger-Ward functional, we elucidate an emergent mixing between different "parities" in time. The simplest case of the conventional s-wave singlet mixed with the odd-frequency triplet state under broken time-reversal symmetry is examined to demonstrate the anomalous structure of the free-energy functional. The induced odd-frequency component alters behaviors of physical quantities from those obtained by neglecting the odd-frequency component. The novel mixed state may also be relevant to strong-coupling superconductivity coexisting with ferromagnetism.

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Hiroaki Kusunose, Masashige Matsumoto, Mikito Koga. 2012-05-25. Strong-Coupling Superconductivity with Mixed Even- and Odd-Frequency Pairing. https://doi.org/10.1103/physrevb.85.174528

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