AQP -seminaari: Quantised Fermi-arc-mediated transport in Weyl semimetal nanowires
Aalto Quantum Physics -seminaari (Nanotalo). Puhuja: Vardan Kaladzhyan (KTH, Stockholm)
We study longitudinal magnetotransport in Weyl semimetal nanowires. We show that depending on radii of nanowires there are two qualitatively different regimes of transport with respect to the chemical potential in the sample. First, for low doping most of the contribution to conductance comes from the Fermi arc surface states, and thus conductance grows linearly with the chemical potential; the flux dependence changes in steps of one quantum of conductance with characteristic interference oscillations. Second, for highly-doped samples the dominant contribution to conductance is quadratic in the chemical potential, and mostly conditioned by the bulk states; the flux dependence shows clearly that both the surface and the bulk states contribute to conductance. The two aforementioned regimes prove that the contribution of Fermi arc surface states is salient and, therefore, crucial for understanding transport properties of finite-size Weyl semimetal systems.