Fluctuation-dissipation theorem for chiral systems in nonequilibrium steady states

Abstract

We consider a three-terminal system with a chiral edge channel connecting the source and drain terminals. Charge can tunnel between the chiral edge and a third terminal. The third terminal is maintained at a different temperature and voltage than the source and drain. We prove a general relation for the current noises detected in the drain and third terminal. It has the same structure as an equilibrium fluctuation-dissipation relation with the nonlinear response I/V in place of the linear conductance. The result applies to a general chiral system and can be useful for detecting "upstream" modes on quantum Hall edges. © 2011 American Physical Society.