The energy spectrum and thermodynamics of the finite spin-1/2 XX chain with Ising-type Impurities

Abstract

The energy spectrum and thermodynamics of two one-dimensional spin systems: the finite XX-chain with periodic boundaries and one zz (Ising) bond, and open ends XX-chain with two zz-impurities at the both ends have been investigated. The conditions for the appearance of the energy states, localized in the vicinity of impurity spins, have been derived. The peculiarities of field and temperature dependences of the basic thermodynamic characteristics of these models have been studied.