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arXiv · 0707.4031

Spin-triplet pairing instability of the spinon Fermi surface in a U(1) spin liquid

Victor Galitski·Yong Baek Kim
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Abstract

Recent experiments on the organic compound κ-(ET)_2Cu_2(CN)_3 have provided a promising example of a two dimensional spin liquid state. This phase is described by a two-dimensional spinon Fermi sea coupled to a U(1) gauge field. We study Kohn-Luttinger-like pairing instabilities of the spinon Fermi surface due to singular interaction processes with twice-the-Fermi-momentum transfer. We find that under certain circumstances the pairing instability occurs in odd-orbital-angular-momentum/spin-triplet channels. Implications to experiments are discussed.

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Victor Galitski, Yong Baek Kim. 2007-07-27. Spin-triplet pairing instability of the spinon Fermi surface in a U(1) spin liquid. https://doi.org/10.1103/physrevlett.99.266403

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