Theory of magnetic excitations in the Kondo lattice
Abstract
Description
We present a theory for the spin excitations of the Kondo lattice. We derive an effective Hamiltonian, which describes Fermionic spin 1/2 charge fluctuations interacting with Bosonic triplet spin fluctuations. We show that already the simplest approximation possible, i.e. replacing the magnon self-energy by the free polarization bubble for the charge excitation Greens function, gives a quantitative description of the `spin gap' and `charge gap' as obtained in numerical calculations for the Kondo insulator.
RevTex-file, 4 PRB pages with 4 embedded eps files. Hardcopies of figures (or the entire manuscript) can be obtained by e-mail request to: eder@physik.uni-wuerzburg.de
RevTex-file, 4 PRB pages with 4 embedded eps files. Hardcopies of figures (or the entire manuscript) can be obtained by e-mail request to: eder@physik.uni-wuerzburg.de