Thermopower with broken time-reversal symmetry
  We show that when non-unitary noise effects are taken into account the thermopower is in general asymmetric under magnetic field reversal, even for non-interacting systems. Our findings are illustrated in the example of a three-dot ring structure pierced by an Aharonov-Bohm flux. 
Keiji Saito, Giuliano Benenti, Giulio Casati, Tomaz Prosen
cond-mat.stat-mech