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Register a new userU(1)_V x U(1)_A symmetry breaking in superconductivity
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Authors
Kosuke Odagiri
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We argue that the general symmetry-breaking pattern in (quasi-)conventional (parity and time-reversal symmetric single-band spin-singlet) superconductivity is given by U(1)_V x U(1)_A -> U(1)_A, where V stands for vector and A stands for axial-vector, as opposed to the breaking of U(1)_Vequiv U(1)_ele/mag by itself as is commonly thought. This symmetry-breaking pattern implies that there will be a Higgs mode which, together with the Goldstone boson that is absorbed by the photon (Meissner effect), characterize the symmetry-breaking dynamics. We obtain a number of strikingly simple analytical results, which amalgamate the findings of the standard BCS and Ginzburg-Landau theories.
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