PHOTOLUMINESCENT SIGNATURE OF ABSORBING MEDIUM WITH DEEP LEVELS BASED UPON ABSORPTION COEFFICIENTS DERIVED FROM PARABOLIC-BAND APPROXIMATIONS

摘要

This paper presents theoretical photoluminescent spectra of absorbing media each with valid quantumstates forming an intermediate band. The novelty here is to illustrate the spectroscopic consequences of multi-gapabsorbers whose quantum states form parabolic bands. Photoluminescence spectroscopy allows the band-edges ofmultiple transition solar cells to be investigated without additional complication of fabricating electrical contacts.Results are presented for absorbers with the same bandgaps, yet with distinct absorption characteristics, distincttemperatures, and distinct lengths. The authors draw two conclusions. First, the photoluminescent intensity of anintermediate band absorber may be appreciable within four distinct and well-separated spectral bands. Second, thefull width at half maximum of the spectral band in the infrared regime approximates the width of the intermediateband.