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arXiv · 1506.04740

Probing excitations in insulators via injection of spin-currents

Shubhayu Chatterjee·Subir Sachdev
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Abstract

We propose a spin transport experiment to measure the low-energy excitations in insulators with spin degrees of freedom, with a focus on detecting ground states that lack magnetic order. A general formalism to compute the spin-current from a metal with a non-equilibrium distribution of spins to an insulator is developed. It is applied to insulating states with and without long range magnetic order, and salient features in the spin-conductance are noted.

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Shubhayu Chatterjee, Subir Sachdev. 2015-07-13. Probing excitations in insulators via injection of spin-currents. https://doi.org/10.1103/physrevb.92.165113

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