Excited States and Their Dynamics in CdSe Quantum Dots Studied by Two-Color 2D Spectroscopy.

ABSTRACT: Quantum dots (QDs) form a promising family of nanomaterials for various applications in optoelectronics. Understanding the details of the excited-state dynamics in QDs is vital for optimizing their function. We apply two-color 2D electronic spectroscopy to investigate CdSe QDs at 77 K within a broad spectral range. Analysis of the electronic dynamics during the population time allows us to identify the details of the excitation pathways. The initially excited high-energy electrons relax with the time constant of 100 fs. Simultaneously, the states at the band edge rise within 700 fs. Remarkably, the excited-state absorption is rising with a very similar time constant of 700 fs. This makes us reconsider the earlier interpretation of the excited-state absorption as the signature of a long-liv

SUBMITTER: Wang Z 

PROVIDER: S-EPMC8842281 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature