Realistic Calculation of the Indirect-Exchange Interaction in Metals

Abstract
It is shown that the indirect-exchange interaction, or Ruderman-Kittel-Kosuya-Yosida (RKKY) interaction, between localized moments in metals can be evaluated numerically for realistic band structures. The numerical method gives results in excellent agreement with the analytical RKKY results for free-electron bands and is applied to the calculation of the indirect-exchange interaction between nuclear moments in Cu. We find the nearest-neighbor exchange-interaction constant to be J=22.6 nK compared to the free-electron RKKY value of J=8.2 nK with the same normalization procedure.