Practical efficiency limits of electroluminescent cooling

Refrigeration is an intrinsic feature of light-emitting diodes, a fact that was recognized decades ago but has so far eluded direct experimental observation at practical power densities. The problem is insufficient external luminescence efficiency; for net cooling to occur, the losses in the device must be close to zero, and a sufficiently efficient LED has yet to materialize. We propose a possible structure for such an LED, and predict that with existing optoelectronic material quality and device processing, electroluminescent refrigeration is not only possible but is potentially more efficient than its solid-state alternatives, particularly at low temperature.