The formation of spatially indirect (interwell) excitons in superlattices (SLs) with different barrier widths (different tunneling coupling) is experimentally investigated in a strong enough magnetic field with the use of photoluminescence (PL), photoluminescence excitation (PLE), reflectance spec tra and time-resolved technique. The experimental conditions for the observation of interwell excitons in SLs without externally breaking inversion symmetry are identified and the distinct excitonic state is found to be located between Is-exciton and the onset of the miniband absorption. Magnetic field; perpendicular to the layers, strongly modifies the interwell and intrawell excitonic states and transforms the system to the weak coupling regime. The effect of interwell exciton conversion into intrawell one due to exciton-exciton collisions has been observed at a high excitation regime and confirmed by time-resolved spectroscopy experiments under pulsed picosecond excitation.
|Journal||PHYSICA STATUS SOLIDI A-APPLIED RESEARCH|
|Publication status||Published - 1997|
Timofeev, V. B., Filin, A. I., Tartakovskii, A. I., Birkedal, D., & Hvam, J. M. (1997). Interwell and intrawell magnetoexcitons in GaAs/AlGaAs superlattices. PHYSICA STATUS SOLIDI A-APPLIED RESEARCH, 164(1), 595-600. https://doi.org/10.1002/1521-396X(199711)164:1<595::AID-PSSA595>3.0.CO;2-1