Spin conductivity of the two-dimensional ferroquadrupolar Heisenberg model

Abstract

Abstract We use the SU(3) Schwinger׳s boson theory to study the spin transport in the S=1 two-dimensional ferroquadrupolar Heisenberg model in the square lattice. We calculate the spin conductivity σ ( ω ) and analyzed the behavior of the AC and DC spin conductivities. The model presents a bilinear and biquadratic exchange interactions. Our results show that the system is an ideal spin conductor for T > 0 , because Drude׳s weight DS (which represents the DC conductivity) is non zero for T > 0 and the AC conductivity given by σ reg ( ω ) tends to the infinity when ω → 0 which also correspond to the DC limit.