A nonlinear-transport perspective of field-induced phase transitions in pentatellurides

Combining topological states of matter with strong electron correlation promises many exotic phenomena such as charge fractionalization, excitonic instability, and axionic excitation. Layered transition-metal pentatellurides ZrTe5 and HfTe5 were found to be close to an accidental topological semimetal phase with low carrier density. Even in a relatively low magnetic field, they can form highly degenerated Landau levels and dramatically enhance the correlation effect of Dirac electrons therein. T...