Asymmetric Anderson model and spin excitations in the Kondo insulator YbB12

作者:Barabanov A F*; Maksimov L A
来源:Journal of Experimental and Theoretical Physics, 2009, 109(1): 95-102.
DOI:10.1134/S1063776109070127

摘要

A cluster problem is analyzed as an example demonstrating that the observed three-mode behavior of spin-triplet excitations in YbB12 can be described by the asymmetric Anderson model with insulating singlet ground state. In the case of an infinite system, it is argued that the behavior of the f subsystem can be analyzed by using an effective Hamiltonian Acurrency sign (J) with direct antiferromagnetic f-f exchange interaction. The spin excitation spectrum is shown to have a minimum at the antiferromagnetic vector, as observed experimentally. A distinctive feature of the analysis is the use of singlet and triplet basis operators.

  • 出版日期2009-7