Evaluation of Auger Limited Behavior in Thermoradiative Cells

The impact of Auger recombination on ther-moradiative cell power density and power conversion efficiency are investigated with simulations based on recombination rates for narrow bandgap semiconductor materials. A crossover point occurs for non-radiatively/radiatively limited cell performance that determines the minimum bandgap energy and corresponding maximum intrinsic carrier density for a given cell temperature. Calculations for HgCdTe as a representative bulk narrow bandgap material spanning the full range of infrared show that the maximum power conversion efficiency and power density for radiatively limited performance are constrained well below the calculated ideal performance limits. This work is expected to serve as a basis to set realistic expectations for thermoradiative cell performance for bulk semiconductor materials, and to highlight the importance of suppressing Auger recombination rates as perhaps the most critical need for improving thermoradiative cells.