Thermal transport through a one-dimensional quantum spin-1/2 chain heterostructure: The role of three-site spin interaction

We study the thermal transport through a quantum spin-1/2 chain heterostructure, which consists of a finite-size chain with two-site isotropic XY interaction and three-site XZX+YZY interaction coupled at its ends to two semi-infinite isotropic XY chains. After performing Jordan-Wigner transformation, we map the original spin Hamiltonian into a fermion Hamiltonian and express the heat current with a nonequilibrium Green’s function formalism. Then, the heat current as functions of the structure parameters are studied in detail. As a result, we observe that a finite magnetic field applied at the finite-size chain can efficiently induce the heat current asymmetry with ΔΩ (ΔΩ is the magnetic field difference between the finite-size chain and the semi-infinite chains). Accordingly, such a magnetic field can be viewed as a switch in manipulating the heat current. Copyright EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2013