The k⋅p effective mass approximation (EMA) predicts large, nearly size-independent exciton oscillator strengths in quantum confined semiconductors. Yet, experimental reports have concluded that the total oscillator strength of the lowest-energy (1S3/21Se) excitons in strongly confined CdSe NQDs is small and strongly size-dependent. Using the optical Stark effect, we show that the oscillator strength of the 1S3/21Se excitonic absorption peak in CdSe NQDs follows the predictions of the EMA. These oscillator strengths enable helicity-selective unsaturated Stark shifts corresponding to femtosecond pseudo-magnetic fields exceeding 100 T.
@article{arxiv.1703.00530,
title = {Optical Stark metrology of CdSe quantum dots: Reconciling the size-dependent oscillator strength with theory},
author = {Yanhao Tang and Mersedeh Saniepay and Chenjia Mi and Rémi Beaulac and John A. McGuire},
journal= {arXiv preprint arXiv:1703.00530},
year = {2017}
}