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Spatiotemporal Carrier Dynamics of Molybdenum Disulfide Nanoflakes : = A Detailed Investigation Using Pump-Probe Microscopy.

Record Type:	Language materials, manuscript : Monograph/item
Title/Author:	Spatiotemporal Carrier Dynamics of Molybdenum Disulfide Nanoflakes :/
Reminder of title:	A Detailed Investigation Using Pump-Probe Microscopy.
Author:	Malizia, Jason Patrick.
Description:	1 online resource (127 pages)
Notes:	Source: Dissertations Abstracts International, Volume: 83-03, Section: B.
Contained By:	Dissertations Abstracts International83-03B.
Subject:	Physical chemistry. -
Online resource:	click for full text (PQDT)
ISBN:	9798535598130

Spatiotemporal Carrier Dynamics of Molybdenum Disulfide Nanoflakes : = A Detailed Investigation Using Pump-Probe Microscopy.
Malizia, Jason Patrick.

Spatiotemporal Carrier Dynamics of Molybdenum Disulfide Nanoflakes :A Detailed Investigation Using Pump-Probe Microscopy. - 1 online resource (127 pages)

Source: Dissertations Abstracts International, Volume: 83-03, Section: B.

Thesis (Ph.D.)--The University of North Carolina at Chapel Hill, 2021.

Includes bibliographical references

Prompted by emerging nanotechnologies, semiconductor nanostructures have been studied by a wide range of optical time-resolved experiments. However, most time-resolved spectroscopies lack spatial resolution and average the excited state dynamics over multiple nanostructures, as well as the heterogeneity present in individual structures. Here, the sub-picosecond temporal resolution of the pump-probe technique is combined with a diffraction-limited light microscope to resolve the ultrafast dynamics of both single MoS2 nanoflakes and individual structural features (such as edges, tears, and steps) present within those structures. The MoS2 nanoflakes studied are ~20 nm thick and a few microns across. Excitation with a 425 nm pump promotes electrons across the band gap at a localized point in a single structure. Monitoring the changes in the intensity of a transmitted 850 nm probe reveals two distinct photoexcited species in the lattice: short lived excitons that decay via exciton-exciton annihilation and long lived free-carriers that decay through traps. The imaging capabilities of the microscope resolve differences in the kinetics at the edges of the MoS2 nanoflakes compared to that of the basal plane. Pump-probe images of individual nanoflakes also reveal a periodic fringe pattern that is most intense at the edge of the flake and decays in amplitude towards the flake's interior. The fringes result from exciton-polariton formation, whereby the probe light couples to excitons formed by pump excitation to form exciton-polaritons.

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2024

Mode of access: World Wide Web

ISBN: 9798535598130Subjects--Topical Terms:

1148725
Physical chemistry.
Subjects--Index Terms:

Carrier dynamicsIndex Terms--Genre/Form:

554714
Electronic books.

Spatiotemporal Carrier Dynamics of Molybdenum Disulfide Nanoflakes : = A Detailed Investigation Using Pump-Probe Microscopy.
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