Electron magnetotransport in disordered Weyl semimetals

QUEST Center event
No
Speaker
Pavel Ostrovsky
Date
22/11/2017 - 15:30 - 14:30Add to Calendar 2017-11-22 14:30:00 2017-11-22 15:30:00 Electron magnetotransport in disordered Weyl semimetals We study magnetotransport in a disordered Weyl semimetal taking into  account localization effects. In the vicinity of a Weyl node, a single  chiral Landau level coexists with a number of conventional non-chiral  levels. Disorder scattering mixes these topologically different modes  leading to peculiar localization effects. Similar interplay of topology  and localization occurs at the edge of a two-dimensional topological  insulator and in carbon nanotubes. We develop a general theory  describing transport phenomena in all these cases. Our theory yields  conductance, shot noise power, and full counting statistics of the  charge transfer. In the case of a Weyl semimetal, we find that  localization is greatly enhanced in a strong magnetic field with the  typical localization length scaling as 1/B. This situation is typical  for all topological conductors with broken time-reversal symmetry.  Systems with preserved time-reversal symmetry (e.g., carbon nanotubes),  sustain at most one topologically protected channel. For this case, we  derive exact distribution function of transmission probabilities based  on the mapping to a certain random-matrix model. *** Nano 9th floor *** NOTE THE DIFFERENT DAY AND LOCATION המחלקה לפיזיקה physics.dept@mail.biu.ac.il Asia/Jerusalem public
Place
*** Nano 9th floor *** NOTE THE DIFFERENT DAY AND LOCATION
Abstract

We study magnetotransport in a disordered Weyl semimetal taking into 
account localization effects. In the vicinity of a Weyl node, a single 
chiral Landau level coexists with a number of conventional non-chiral 
levels. Disorder scattering mixes these topologically different modes 
leading to peculiar localization effects. Similar interplay of topology 
and localization occurs at the edge of a two-dimensional topological 
insulator and in carbon nanotubes. We develop a general theory 
describing transport phenomena in all these cases. Our theory yields 
conductance, shot noise power, and full counting statistics of the 
charge transfer. In the case of a Weyl semimetal, we find that 
localization is greatly enhanced in a strong magnetic field with the 
typical localization length scaling as 1/B. This situation is typical 
for all topological conductors with broken time-reversal symmetry. 
Systems with preserved time-reversal symmetry (e.g., carbon nanotubes), 
sustain at most one topologically protected channel. For this case, we 
derive exact distribution function of transmission probabilities based 
on the mapping to a certain random-matrix model.

תאריך עדכון אחרון : 03/11/2017