title: Direct observation of valley hybridization and universal symmetry of graphene with mesoscopic conductance fluctuations.
abstract: In graphene, the valleys represent spinlike quantities and can act as a physical resource in valley-based electronics to produce novel quantum computation schemes. Here we demonstrate a direct route to tune and read the valley quantum states of disordered graphene by measuring the mesoscopic conductance fluctuations. We show that the conductance fluctuations in graphene at low temperatures are reduced by a factor of 4 when valley triplet states are gapped in the presence of short-range potential scatterers at high carrier densities. We also show that this implies a gate tunable universal symmetry class that outlines a fundamental feature arising from graphene's unique crystal structure.
authors.affiliation: Department of Physics, Indian Institute of Science, Bangalore 560 012, India. palat@phys.ethz.ch
authors.forename: Atindra Nath
authors.initials: AN
authors.lastname: Pal
authors.forename: Vidya
authors.initials: V
authors.lastname: Kochat
authors.forename: Arindam
authors.initials: A
authors.lastname: Ghosh