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arXiv · 1806.06112

Vibrational Coupling Modifies Spectral Diffusion in Core-Shell Colloidal Quantum Dots

A. Liu·D. B. Almeida·W. K. Bae·L. A. Padilha·S. T. Cundiff
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Abstract

We perform two-dimensional coherent spectroscopy on CdSe/CdZnS core/shell colloidal quantum dots at cryogenic temperatures. In the two-dimensonal spectra, sidebands due to electronic coupling with CdSe lattice LO-phonon modes are observed that have evolutions deviating from the exponential dephasing expected from Markovian spectral diffusion. Comparison to simulations provides further evidence that the LO-phonon mode coupling itself significantly modifies the exciton lineshapes and results in the underlying spectral diffusion on ultrafast timescales.

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A. Liu, D. B. Almeida, W. K. Bae, L. A. Padilha, S. T. Cundiff. 2018-06-15. Vibrational Coupling Modifies Spectral Diffusion in Core-Shell Colloidal Quantum Dots. https://doi.org/10.1103/physrevlett.123.057403

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