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The duration of transient absorption spectroscopy measurements typically limits the types of systems for which the excited state dynamics can be measured. We present a single-shot transient absorption (SSTA) instrument with a spatially encoded 60 ps time delay range and a 100 nm spectral range that is capable of acquiring a transient spectrum in 20 s. We describe methods to spatially overlap the flat-top pump and probe beams at the sample plane, calibrate the spatially encoded time delay, and correct for non-uniform excitation density. SSTA measurements of organic materials in solution and film demonstrate this technique.
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Single-shot transient absorption spectroscopy of an organic film
ABSTRACT We report single-shot transient absorption (SSTA) measurements of an organic film of 3,3’-Diethyloxatricarbocyanine iodide (DOTCI). In SSTA, the pump-probe time delay is spatially encoded by using a tilted pump pulse. Translation of the sample during SSTA measurements averages over any spatial heterogeneity in the film. We demonstrate that exciton dynamics measured with the single-shot technique agrees with traditional transient absorption measurements of the same film. A signal-to-noise ratio of ∼40 is achieved in 10 s. The ability to measure exciton dynamics in organic films will enable future SSTA measurements of exciton dynamics during the molecular aggregation events that result in film formation.
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- Award ID(s):
- 1752129
- PAR ID:
- 10086522
- Date Published:
- Journal Name:
- MRS Advances
- Volume:
- 3
- Issue:
- 59
- ISSN:
- 2059-8521
- Page Range / eLocation ID:
- 3453 to 3457
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1557/adv.2018.402
