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Spin ordering quantum transitions of superconductors in a magnetic field

Eugene Demler·Subir Sachdev·Ying Zhang
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Abstract

We argue that recent neutron scattering measurements by Lake et. al. (Science 291, 1759 (2001)) of the spin excitation spectrum of LSCO in a magnetic field can be understood in terms of proximity to a phase with co-existing superconductivity and spin density wave order. We present a general theory for such quantum transitions, and argue that their low energy spin fluctuations are controlled by a singular correction from the superflow kinetic energy, acting in the region outside the vortex cores. We propose numerous experimental tests of our theory.

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Eugene Demler, Subir Sachdev, Ying Zhang. 2001-06-01. Spin ordering quantum transitions of superconductors in a magnetic field. https://doi.org/10.1103/physrevlett.87.067202

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