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Title: The Role of Electronic and Phononic Excitation in the Optical Response of Monolayer WS 2 after Ultrafast Excitation

Abstract

We study transient changes of the optical response of WS 2 monolayers by femtosecond broadband pump–probe spectroscopy. Time-dependent absorption spectra are analyzed by tracking the line width broadening, bleaching, and energy shift of the main exciton resonance as a function of time delay after the excitation. Two main sources for the pump-induced changes of the optical response are identified. Specifically, we find an interplay between modifications induced by many-body interactions from photoexcited carriers and by the subsequent transfer of the excitation to the phonon system followed by cooling of the material through the heat transfer to the substrate.

Authors:
ORCiD logo [1];  [2];  [3];  [3];  [3]
  1. Columbia Univ., New York, NY (United States). Dept. of Physics and Electrical Engineering; Technische Univ. of Dortmund (Germany). Dept. of Physics
  2. Columbia Univ., New York, NY (United States). Dept. of Physics and Electrical Engineering; Univ. of Regensburg (Germany). Dept. of Physics
  3. Columbia Univ., New York, NY (United States). Dept. of Physics and Electrical Engineering; Stanford Univ., CA (United States). Dept. of Applied Physics; SLAC National Accelerator Lab., Menlo Park, CA (United States)
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE; German Research Foundation (DFG); National Science Foundation (NSF)
OSTI Identifier:
1353103
Grant/Contract Number:
DGE-1069240; FA9550-14-1-0268; AC02-76SF00515
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nano Letters
Additional Journal Information:
Journal Volume: 17; Journal Issue: 2; Journal ID: ISSN 1530-6984
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; atomically thin 2D materials; ultrafast spectroscopy; carrier and phonon dynamics

Citation Formats

Ruppert, Claudia, Chernikov, Alexey, Hill, Heather M., Rigosi, Albert F., and Heinz, Tony F. The Role of Electronic and Phononic Excitation in the Optical Response of Monolayer WS2 after Ultrafast Excitation. United States: N. p., 2017. Web. doi:10.1021/acs.nanolett.6b03513.
Ruppert, Claudia, Chernikov, Alexey, Hill, Heather M., Rigosi, Albert F., & Heinz, Tony F. The Role of Electronic and Phononic Excitation in the Optical Response of Monolayer WS2 after Ultrafast Excitation. United States. doi:10.1021/acs.nanolett.6b03513.
Ruppert, Claudia, Chernikov, Alexey, Hill, Heather M., Rigosi, Albert F., and Heinz, Tony F. Fri . "The Role of Electronic and Phononic Excitation in the Optical Response of Monolayer WS2 after Ultrafast Excitation". United States. doi:10.1021/acs.nanolett.6b03513. https://www.osti.gov/servlets/purl/1353103.
@article{osti_1353103,
title = {The Role of Electronic and Phononic Excitation in the Optical Response of Monolayer WS2 after Ultrafast Excitation},
author = {Ruppert, Claudia and Chernikov, Alexey and Hill, Heather M. and Rigosi, Albert F. and Heinz, Tony F.},
abstractNote = {We study transient changes of the optical response of WS2 monolayers by femtosecond broadband pump–probe spectroscopy. Time-dependent absorption spectra are analyzed by tracking the line width broadening, bleaching, and energy shift of the main exciton resonance as a function of time delay after the excitation. Two main sources for the pump-induced changes of the optical response are identified. Specifically, we find an interplay between modifications induced by many-body interactions from photoexcited carriers and by the subsequent transfer of the excitation to the phonon system followed by cooling of the material through the heat transfer to the substrate.},
doi = {10.1021/acs.nanolett.6b03513},
journal = {Nano Letters},
number = 2,
volume = 17,
place = {United States},
year = {Fri Jan 06 00:00:00 EST 2017},
month = {Fri Jan 06 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
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Citation Metrics:
Cited by: 14works
Citation information provided by
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