Performances of far- and near-field thermophotonic refrigeration devices from the detailed-balance approach

We study a near-field thermophotonic (NF-TPX) refrigerating device, consisting of a light-emitting diode and a photovoltaic cell in close proximity. Calculations are performed in the frame of the detailed-balance approach. We study how thermal radiation, separation distance, and light-emitting diode temperature can affect both cooling power and coefficient of performance. More specifically, we assess the impact of bandgap energy and quantum efficiency for an artificial material on those cooling performances. For a particular device made of GaAs and/or AlGaAs we show that, in the near-field regime, the cooling power can be increased by one order of magnitude compared to far field. However, a 10% reduction of the quantum efficiency can lead to a decrease of the cooling power by two orders of magnitude. Finally, we compare existing literature data on electroluminescent, TPX and thermoelectric cooling with our detailed-balance prediction, which highlights design-rule requirements for NF-TPX cooling devices.