Anomalous Spin Transport Properties of Gapped Dirac Electrons with Tilting

Abstract

The anomalous spin transport coefficients of gapped Dirac electrons are studied with application to a quasi-two-dimensional organic conductor $\alpha$-(BETS)${}_2$I${}_3$ in mind. In the presence of a gap induced by spin-orbit interaction, we show that the effective Hamiltonian is similar to the model considered by Kane and Mele with additional tilting. With this effective Hamiltonian, conductivity tensors up to the linear order of the applied magnetic field are obtained analytically using the microscopic linear response theory or Kubo formula. It is shown that spin Hall conductivity and anomalous diagonal spin conductivity proportional to the magnetic field become nonzero in this system, which are written in terms of the Berry curvature and orbital magnetic moment.The estimated values of spin conductivities using typical parameters turn out to be comparable to the spin Hall conductivity in Pt.

References in corpus (12)

• Quantum Theory of Orbital Magnetization and its Generalization to Interacting Systems
• Transport Properties and Diamagnetism of Dirac Electrons in Bismuth
• Observation of an anisotropic Dirac cone reshaping and ferrimagnetic spin polarization in an organic conductor
• Anomalous Orbital Magnetism and Hall Effect of Massless Fermions in Two Dimension
• Importance of Spin-Orbit Coupling in Organic BEDT-TTF and BEDT-TSF Salts
• Interband Effects of Magnetic Field on Hall Effects for Dirac Electrons in Bismuth
• Spin-Hall Effect and Diamagnetism of Dirac Electrons
• Giant orbital diamagnetism of three-dimensional Dirac electrons in Sr${}_3$PbO antiperovskite
• Spin-Hall Effect and Diamagnetism of Anisotropic Dirac Electrons in Solids
• Edge states in the three-quarter filled system, $\alpha$-(BEDT-TTF)${}_2$I${}_3$
• Predicted photoinduced pair annihilation of emergent magnetic charges in the organic salt $\alpha$-(BEDT-TTF)${}_2$I${}_3$ irradiated by linearly polarized light
• Possible Nonlinear Anomalous Thermoelectric Effect in Organic Massive Dirac Fermion System