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arXiv · 0708.1950

Kondo effect in an Antiferromagnetic metal

Vivek Aji·Chandra Varma·Ilya Vekhter
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Abstract

We study the fate of a spin-1/2 impurity in the itinerant antiferromagnetic metallic phase via a renormalization group analysis and a variational calculation. The local moment - conduction electron interaction hamiltonian in an antiferromagnetic metal is spin non-conserving. We show that for a general location of the impurity, the Kondo singularities still occur, but the ground state has a partially unscreened moment. We calculate the magnitude of this residual moment and the variation of the spin polarization with energy for a substitutional impurity as a function of the staggered magnetization. The usual Kondo effect only occurs if the impurity is placed at points where the magnetization is zero.

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Vivek Aji, Chandra Varma, Ilya Vekhter. 2008-06-05. Kondo effect in an Antiferromagnetic metal. https://arxiv.org/abs/0708.1950

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