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DOE OSTI · 1775096

Circularly Polarized Optical Stark Effect in CdSe Colloidal Quantum Wells

Diroll, Benjamin T.
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Abstract

Colloidal quantum wells, or nanoplatelets, exhibit large, circularly polarized optical Stark effects under sub-band-gap femtosecond illumination. The optical Stark effect is measured for CdSe colloidal quantum wells of several thicknesses and separately as a measure of pump photon energy, pump fluence, and temperature. These measurements show that optical Stark effects in colloidal quantum wells shift the absorption features up to 5 meV, at the intensities up to 2.9 GW.cm -2 and large detuning (>400 meV) of the pump photon energy from the band edge absorption. Optical Stark shifts are underpinned by large transition dipoles of the colloidal quantum wells (mu = 15-23 D), which are larger than those of any reported colloidal quantum dots or epitaxial quantum wells. The rapid (<500 fs), narrow band blue shift of the excitonic features under circular excitation indicates the viability of these materials beyond light emission such as spintronics or all-optical switching.

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77 NANOSCIENCE AND NANOTECHNOLOGYAC Stark EffectAutler-Townes EffectCircular DichroismNanoplateletsOptical Stark Effect

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Diroll, Benjamin T.. 2020-10-29. Circularly Polarized Optical Stark Effect in CdSe Colloidal Quantum Wells. https://doi.org/10.1021/acs.nanolett.0c02409

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