Study of the Natural Auger Suppression Mechanism in Heterostructures through Heteroboundary Engineering

Abstract

Planar superlattice devices revolutionized our approach to solid-state technology by reducing the Shockley-Read-Hall losses to negligible levels. Despite these achievements, significant efficiency losses are found in current devices presumably caused by the Auger recombinations. This work present the theoretical considerations of the Auger recombination suppression through heterostructure engineering. It is found that Auger recombinations are suppressed through the heterobarrier-carrier interactions. It is shown that a minima in Auger recombinations exists in type-II and III heterostructures, and can be reached through proper conduction and valence band alignments. Furthermore, the careful consideration of the heterostructure enables natural Auger suppression for high operating temperatures. Dark current based on the optimized heterostructure was computed and found to be over an order of magnitude below the currently reported measurements for the superlattice and QD devices. This research provides crucial information about the underlying physics behind the Auger recombination, enabling future superlattice and quantum dot device optimization.

Fundamental Limits to Far-Infrared Lasing in Auger-Suppressed HgCdTe Quantum Wells

“…The Auger activation threshold E th depends strongly on the energy-momentum relation for electrons and holes, ε p . Therefore, engineering the band structure by tuning strain, 13 boundary profile of quantum wells 14 and dots, 15 and their composition remained so far the most efficient way to suppress AR. At the same time, there exists a peculiar type of band dispersion where AR is prohibited by energy-momentum conservation laws.…”

Solar Thermoradiative-Photovoltaic Energy Conversion

“…In particular, the effect of TR temperature on nonradiative losses could be significant depending on the TR material [47,71]. Auger losses can increase significantly as temperature increases, which may require the use of strategies for Auger suppression such as the use of a p-i-n diode to reduce carrier concentrations in the active region [72,73], interface-induced Auger suppression in type-II and type-III heterostructures [74][75][76], or careful engineering of the confinement potential in nanostructurebased devices [77]. The bandgap of a device also generally shifts with temperature, which could require different material compositions of the TR and PV cells in order to align their bandgaps.…”