Résumé
Multisubband plasmon (MSP) modes in heavily doped InAs/GaSb broken-gap quantum wells grown via molecular beam epitaxy (MBE) are investigated. An eight-band (k) over right arrow . (p) over right arrow semiclassical model accurately predicts ellipsometric spectra, reflecting strong subband hybridization and nonparabolicity. In contrast, single-band plasmon models show qualitative discrepancies with experiment, even with adjusted effective masses. These findings highlight the potential of broken-gap wells for quantum technologies leveraging interband coupling and wavefunction hybridization.