Thermoelectric corrections to quantum voltage measurement

A generalization of B\"uttiker's voltage probe concept for nonzero temperatures is an open third terminal of a quantum thermoelectric circuit. An explicit analytic expression for the thermoelectric correction to an ideal quantum voltage measurement in linear response is derived and interpreted in terms of local Peltier cooling/heating within the nonequilibrium system. The thermoelectric correction is found to be large (up to 24% of the peak voltage) in a prototypical ballistic quantum conductor (graphene nanoribbon). The effects of measurement nonideality are also investigated. Our findings have important implications for precision local electrical measurements.