Application of impedance matching for enhanced transmitted power in a thermophotovoltaic system

Based on the impedance matching condition, we propose a few configurations that can greatly enhance radiation power transfer from the emitter to the photovoltaic (PV) cell for a near-field based thermophotovoltaic (TPV) system. In addition to the emitter and PV cell, these configurations involve the use of additional materials that support resonant modes, such as a metallic material whose dielectric function can be described by a Drude model, or a dielectric material whose dielectric function can be approximated by a Lorentz oscillator model. We show that by coating the PV cell both on the front and back sides with Lorentz materials, the transferred power can be 2.5 times larger than that without any decorations. When Drude metals are included in the configuration, the optimal transferred power can be 3 times larger than the system without additional materials. We find the key to enhance transmitted power is to place a thin layer of Drude/Lorentz material on the front side (facing the emitter) of the PV cell.