Active Peltier Coolers Based on Correlated and Magnon-Drag Metals

Active cooling systems use electrical work to bring a hot device (such as an integrated circuit) down to near ambient temperature by draining heat from the hot area of the device to a passive heat sink. Commercial thermoelectric modules are optimized for refrigeration, and are not ideal for active cooling. Refrigeration maintains a temperature that is below the ambient temperature in a device (such as a kitchen refrigerator) by pumping heat from the cold area of the device to a heat sink. The thermoelectric figure of merit zT is used traditionally to evaluate the performance of thermoelectric modules, including refrigeration modules. But it is not a good indicator of the performance of active cooling materials. Here, we describe an efficient, all-solid-state active cooler based on the Peltier effect in metals with high thermoelectric power factor due to electron correlation effects (Ce_{Pd 3}) or magnon drag (Co ) and high passive thermal conductivity. We show theoretically and experimentally that the effective thermal conductance under applied current can exceed the limits imposed by Fourier's heat conduction law. The designed device measures an effective thermal conductance that is an order of magnitude larger than the passive thermal conductance at ΔT = 1 K with the dynamic response of 4 s.