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Jian-hua Wang

Publications and source records attributed to Jian-hua Wang.

3 recordsLinked to original sources

Seiberg-Witten map and quantum phase effects for neutral Dirac particle on noncommutatiave plane

We provide a new approach to study the noncommutative effects on the neutral Dirac particle with anomalous magnetic or electric dipole moment on the noncommutative plane. The advantages of this approach are demonstrated by investigating the noncommutative corrections on the Aharonov-Casher and He-McKellar-Wilkens effects. This approach is based on the effective $U(1)$ gauge symmetry for the electrodynamics of spin on the two dimensional space. The Seiberg-Witten map for this symmetry is then employed when we study the noncommutative corrections. Because the Seiberg-Witten map preserves the gauge symmetry, the noncommutative corrections can be defined consistently with the ordinary phases. Based on this approach we find the noncommutative corrections on the Aharonov-Casher and He-McKellar-Wilkens phases consist of two terms. The first one depends on the beam particle velocity and consistence with the previous results. However the second term is velocity-independent and then completely new. Therefore our results indicate it is possible to investigate the noncommutative space by using ultra-cold neutron interferometer in which the velocity-dependent term is negligible. Furthermore, both these two terms are proportional to the ratio between the noncommutative parameter $θ$ and the cross section $A_{e/m}$ of the electrical/magnetic charged line enclosed by the trajectory of beam particles. Therefore the experimental sensitivity can be significantly enhanced by reduce the cross section of the charge line $A_{e/m}$.

hep-th↗

Deformations of the spin currents by topological screw dislocation and cosmic dispiration

We study the spin currents induced by topological screw dislocation and cosmic dispiration. By using the extended Drude model, we find that the spin dependent forces are modified by the nontrivial geometry. For the topological screw dislocation, only the direction of spin current is bended by deforming the spin polarization vector. In contrast, the force induced by cosmic dispiration could affect both the direction and magnitude of the spin current. As a consequence, the spin-Hall conductivity doesn't receive corrections from screw dislocation.

cond-mat.mes-hall↗

Influences of Topological Defect on Spin Hall Effect

We study the influence of topological defect on the spin current as well as the spin Hall effect. We find that the nontrivial deformation of the space-time due to topological defect can generate a spin dependent current which then induces an imbalanced accumulation of spin states on the edges of sample. The corresponding spin-Hall conductivity has also been calculated for the topological defect of a cosmic string. Comparing to the ordinary value, a correction which is linear with mass density of the cosmic string appears. Our approach to the dynamics of non-relativistic spinor in the presence of a topological defect is based on the Foldy-Wouthuysen transformation. The spin current is obtained in by using the extended Drude model which is independent of the scattering mechanism.

cond-mat.mes-hall↗