Excitonic Bloch-Siegert shift in CsPbI₃ perovskite quantum dots.

ABSTRACT: Coherent interaction between matter and light field induces both optical Stark effect and Bloch-Siegert shift. Observing the latter has been historically challenging, because it is weak and is often accompanied by a much stronger Stark shift. Herein, by controlling the light helicity, we can largely restrict these two effects to different spin-transitions in CsPbI₃ perovskite quantum dots, achieving room-temperature Bloch-Siegert shift as strong as 4 meV with near-infrared pulses. The ratio between the Bloch-Siegert and optical Stark shifts is however systematically higher than the prediction by the non-interacting, quasi-particle model. With a model that explicitly accounts for excitonic effects, we quantitatively reproduce the experimental observations. This model depicts a un

SUBMITTER: Li Y 

PROVIDER: S-EPMC9500032 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature