Effects of Interactions with Cyclic Solvent Molecules on Optical Dephasing of CdSe/ZnS Colloidal Quantum Dots Detected by Femtosecond Four-Wave Mixing Spectroscopy

We have studied the effects of interactions with cyclic solvent molecules on the optical dephasing of CdSe/ZnS colloidal quantum dots (QDs) by femtosecond four-wave mixing spectroscopy. We have found that the interactions with the cyclic solvents without $\pi$-bonds result in unexpectedly long dephasing times of QDs even at room temperature, while the interactions with the cyclic solvents including $\pi$-bonds make the optical dephasing of QDs extremely fast with a dephasing time of less than our time resolution.