Year: 2007
Type: article
Abstract: We report on the unusual nature of the $\ensuremath{\nu}=0$ state in the integer quantum Hall effect (QHE) in graphene and show that electron transport in this regime is dominated by counterpropagating edge states. Such states, intrinsic to massless Dirac quasiparticles, manifest themselves in a large longitudinal resistivity ${\ensuremath{\rho}}_{xx}\ensuremath{\gtrsim}h/{e}^{2}$, in striking contrast to ${\ensuremath{\rho}}_{xx}$ behavior in the standard QHE. The $\ensuremath{\nu}=0$ state in graphene is also predicted to exhibit pronounced fluctuations in ${\ensuremath{\rho}}_{xy}$ and ${\ensuremath{\rho}}_{xx}$ and a smeared zero Hall plateau in ${\ensuremath{\sigma}}_{xy}$, in agreement with experiment. The existence of gapless edge states puts stringent constraints on possible theoretical models of the $\ensuremath{\nu}=0$ state.
Source: Physical Review Letters
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2105507800