Pulsed Ettingshausen Cooling in Bismuth

The Ettingshausen cooling in single-crystal bismuth was investigated using pulsed currents far in excess of the equilibrium value. At 80K, transient cooling of nearly five times the equilibrium value was observed using rectangular current pulses. By using ramp-shaped pulses even larger transient cooling was observed. The authors suggest that this phenomenon may be due to the localised nature of the generation and recombination of the carriers at the sample surface.