Persistent versus dissipative currents in open quantum systems*

The Aharonov-Bohm (AB) effect on the thermoelectric properties and currents of three-terminal quantum devices is investigated. General expressions of currents of heat and charge are derived using nonequilibrium Green's functions, and applied to calculate the thermoelectric response of a model quantum thermocouple.

It is shown that the AB effect can generate a large thermoelectric response in a device with particle-hole symmetry (nominally with no thermoelectric properties)  as well as modifying the external electric and thermal currents of the device, the AB effect also induces persistent electric and thermal currents. One might expect that a persistent electric current in a quantum thermocouple, through the Peltier effect, could lead to persistent Peltier cooling, violating the 1st and 2nd Laws of Thermodynamics. However, this apparent paradox is resolved by elucidating the distinction between persistent and dissipative currents in quantum thermoelectrics.