posted on 2020-11-10, 18:13authored byIvan D. Avdeev, Mikhail O. Nestoklon, Serguei V. Goupalov
We
study the exciton fine structure in quantum dots of multivalley
lead chalcogenides. We demonstrate that intervalley electron–hole
exchange interaction, ignored in previous studies, dramatically modifies
the exciton fine structure and leads to appearance of the ultrabright
valley-symmetric spin-triplet exciton state dominating interband optical
absorption. Valley mixing leads to brightening of other symmetry-allowed
spin-triplet states which dominate low-temperature photoluminescence.