Second hidden triplet-singlet crossover of charged excitons in n-doped (Cd,Mn)Te/(Cd,Mg)Te in ultra-high magnetic fields

摘要

We studied charged excitons realized in dilute magnetic semiconductor single-quantum wells (Cd,Mn)Te/ (Cd,Mg)Te in high magnetic fields by photoluminescenee (PL) measurements. We assigned two PL peaks which appeared in high magnetic fields as the singlet and the triplet charged excitons, respectively. It was shown from our PL analysis that the second hidden crossover between the triplet and the singlet charged excitons took place above 60 T. The singlet charged exciton transition was found to be the lowest energy in a higher magnetic side. Linear increase in the conduction-electron g factor with increasing magnetic field was deduced from the intensity ratio of two PL lines in magnetic fields up to 140 T.