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Indirect RKKY Interaction in the Nearly Nested Fermi Liquid

D. N. Aristov·S. V. Maleyev
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Abstract

The indirect RKKY interaction in a layered metal with nearly nested (almost squared) Fermi surface is evaluated analytically. The final expressions are obtained in closed form as a combination of Bessel functions. We show that the expected ``2k_F'' oscillations occur as the far asymptote of our expressions, where a value of the effective Fermi momentum k_F depends on the direction in r-space. We demonstrate the existence of the intermediate asymptote of the interaction which is of the sign-reversal antiferromagnetic type. This part of RKKY interaction is the only term surviving in the limit of exact nesting. A good accordance of our analytical formulas with numerical findings is found until the interatomic distances.

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D. N. Aristov, S. V. Maleyev. 1999-10-15. Indirect RKKY Interaction in the Nearly Nested Fermi Liquid. https://doi.org/10.1016/s0921-4526(99)02475-8

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