谢心澄-威尔半金属的量子输运

主讲人:谢心澄

标题:威尔半金属的量子输运    

概要:

We study the scattering and disorder effect in the WSMs. In one respect, we predict the Goos-Hänchen shift and the Imbert-Fedorov exist at the interface of two WSMs after reflection. Interestingly, we find that the IF shift actually originates from the topological effect of the system, and the topological IF shift can be utilized to characterize the Weyl semimetals, design valleytronic devices of high efficiency, and measure the Berry curvature of the system. Moreover, our studies show that the topological IF shift also influences the single impurity scattering cross-section and can further give rise to exotic transport properties of WSMs. In another respect, we study the disorder induced localization in WSMs, and find three exotic phase transitions: (i) two Weyl nodes near the Brillouin zone boundary can be annihilated by disorder scattering, resulting in a transition from a WSM to a 3D quantum anomalous Hall state; (ii) when the two Weyl nodes are well separated in momentum space, the disorder induced bulk extended states can give rise to a direct transition from a WSM to a 3D diffusive anomalous Hall metal; (iii) disorder can close the gap of trivial insulator, and leads to the emergence of two Weyl nodes, which manifests as a transition from a normal band insulator to a WSM. Finally, the magneto-resistance beyond the quantum limit is studied and is found that it shows the discrete scale invariance and logB oscillation.