Effect of Mismatched Electron-Hole Effective Masses on Superfluidity in Double Layer Solid-State Systems.

Conti, Sara; Perali, Andrea; Peeters, François M.; Neilson, David

Superfluidity has been predicted and now observed in a number of different electron-hole double-layer semiconductor heterostructures. In some of the heterostructures, such as GaAs and Ge-Si electron-hole double quantum wells, there is a strong mismatch between the electron and hole effective masses. We systematically investigate the sensitivity to unequal masses of the superfluid properties and the self-consistent screening of the electron-hole pairing interaction. We find that the superfluid properties are insensitive to mass imbalance in the low density BEC regime of strongly-coupled boson-like electron-hole pairs. At higher densities, in the BEC-BCS crossover regime of fermionic pairs, we find that mass imbalance between electrons and holes weakens the superfluidity and expands the density range for the BEC-BCS crossover regime. This permits screening to kill the superfluid at a lower density than for equal masses.

ELECTRONS; SUPERFLUIDITY; SOLID state chemistry; SEMICONDUCTORS; HETEROSTRUCTURES; QUANTUM wells

Condensed Matter, 2021, Vol 6, Issue 2, p1

2410-3896

Academic Journal

10.3390/condmat6020014