Optical gain enhancement and wavefunction confinement tuning in AlSb/InGaAsP/GaAsSb heterostructures Amit Kumar Singh, Rohit Singh, Kulwant Singh and Amit Rathi Eur. Phys. J. B, 94 6 (2021) 123 Published online: 06 June 2021 DOI: 10.1140/epjb/s10051-021-00131-w