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SO(4) Theory of Competition between Triplet Superconductivity and Antiferromagnetism in Bechgaard Salts

Daniel Podolsky·Ehud Altman·Timofey Rostunov·Eugene Demler
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Abstract

Motivated by recent experiments with Bechgaard salts, we investigate the competition between antiferromagnetism and triplet superconductivity in quasi one-dimensional electron systems. We unify the two orders in an SO(4) symmetric framework, and demonstrate the existence of such symmetry in one-dimensional Luttinger liquids. SO(4) symmetry, which strongly constrains the phase diagram, can explain coexistence regions between antiferromagnetic, superconducting, and normal phases, as observed in (TMTSF)$_2$PF$_6$. We predict a sharp neutron scattering resonance in superconducting samples.

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Daniel Podolsky, Ehud Altman, Timofey Rostunov, Eugene Demler. 2004-09-20. SO(4) Theory of Competition between Triplet Superconductivity and Antiferromagnetism in Bechgaard Salts. https://doi.org/10.1103/physrevlett.93.246402

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