Femtosecond to picosecond transient effects in WSe2 observed by pump-probe angle-resolved photoemission spectroscopy

Liu, Ro -Ya; Ogawa, Yu; Chen, Peng; Ozawa, Kenichi; Suzuki, Takeshi; Okada, Masaru; Someya, Takashi; Ishida, Yukiaki; Okazaki, Kozo; Shin, Shik; Chiang, Tai -Chang; Matsuda, Iwao

doi:10.1038/s41598-017-16076-z

Title: Femtosecond to picosecond transient effects in WSe₂ observed by pump-probe angle-resolved photoemission spectroscopy

Abstract

Time-dependent responses of materials to an ultrashort optical pulse carry valuable information about the electronic and lattice dynamics; this research area has been widely studied on novel two-dimensional materials such as graphene, transition metal dichalcogenides (TMDs) and topological insulators (TIs). We report herein a time-resolved and angle-resolved photoemission spectroscopy (TRARPES) study of WSe₂, a layered semiconductor of interest for valley electronics. The results for below-gap optical pumping reveal energy-gain and -loss Floquet replica valence bands that appear instantaneously in concert with the pump pulse. Energy shift, broadening, and complex intensity variation and oscillation at twice the phonon frequency for the valence bands are observed at time scales ranging from the femtosecond to the picosecond and beyond. Furthermore, the underlying physics is rich, including ponderomotive interaction, dressing of the electronic states, creation of coherent phonon pairs, and diffusion of charge carriers – effects operating at vastly different time domains.

Authors:

Liu, Ro -Ya ^[1]; Ogawa, Yu ^[1]; Chen, Peng ^[2]; Ozawa, Kenichi ^[3]; Suzuki, Takeshi ^[1]; Okada, Masaru ^[1]; Someya, Takashi ^[1]; Ishida, Yukiaki ^[1];

^[1]; Shin, Shik ^[1]; Chiang, Tai -Chang ^[4]; Matsuda, Iwao ^[1]

The Univ. of Tokyo, Chiba (Japan)
Univ. of Illinois at Urbana-Champaign, Urbana, IL (United States)
Tokyo Institute of Technology, Tokyo (Japan)
The Univ. of Tokyo, Chiba (Japan); Univ. of Illinois at Urbana-Champaign, Urbana, IL (United States)

Publication Date:: 2017-11-22

Research Org.:: Univ. of Illinois at Urbana-Champaign, IL (United States)

Sponsoring Org.:: USDOE

OSTI Identifier:: 1500108

Grant/Contract Number:: FG02-07ER46383

Resource Type:: Accepted Manuscript

Journal Name:: Scientific Reports

Additional Journal Information:: Journal Volume: 7; Journal Issue: 1; Journal ID: ISSN 2045-2322

Publisher:: Nature Publishing Group

Country of Publication:: United States

Language:: English

Subject:: 36 MATERIALS SCIENCE

Citation Formats


                    Liu, Ro -Ya, Ogawa, Yu, Chen, Peng, Ozawa, Kenichi, Suzuki, Takeshi, Okada, Masaru, Someya, Takashi, Ishida, Yukiaki, Okazaki, Kozo, Shin, Shik, Chiang, Tai -Chang, and Matsuda, Iwao. Femtosecond to picosecond transient effects in WSe2 observed by pump-probe angle-resolved photoemission spectroscopy.  United States: N. p., 2017. 
Web.  doi:10.1038/s41598-017-16076-z.

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                    Liu, Ro -Ya, Ogawa, Yu, Chen, Peng, Ozawa, Kenichi, Suzuki, Takeshi, Okada, Masaru, Someya, Takashi, Ishida, Yukiaki, Okazaki, Kozo, Shin, Shik, Chiang, Tai -Chang, & Matsuda, Iwao. Femtosecond to picosecond transient effects in WSe2 observed by pump-probe angle-resolved photoemission spectroscopy.  United States.  https://doi.org/10.1038/s41598-017-16076-z

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                    Liu, Ro -Ya, Ogawa, Yu, Chen, Peng, Ozawa, Kenichi, Suzuki, Takeshi, Okada, Masaru, Someya, Takashi, Ishida, Yukiaki, Okazaki, Kozo, Shin, Shik, Chiang, Tai -Chang, and Matsuda, Iwao. Wed .  
"Femtosecond to picosecond transient effects in WSe2 observed by pump-probe angle-resolved photoemission spectroscopy".  United States.  https://doi.org/10.1038/s41598-017-16076-z.  https://www.osti.gov/servlets/purl/1500108.

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@article{osti_1500108,

  title        = {Femtosecond to picosecond transient effects in WSe2 observed by pump-probe angle-resolved photoemission spectroscopy},

  author       = {Liu, Ro -Ya and Ogawa, Yu and Chen, Peng and Ozawa, Kenichi and Suzuki, Takeshi and Okada, Masaru and Someya, Takashi and Ishida, Yukiaki and Okazaki, Kozo and Shin, Shik and Chiang, Tai -Chang and Matsuda, Iwao},

  abstractNote = {Time-dependent responses of materials to an ultrashort optical pulse carry valuable information about the electronic and lattice dynamics; this research area has been widely studied on novel two-dimensional materials such as graphene, transition metal dichalcogenides (TMDs) and topological insulators (TIs). We report herein a time-resolved and angle-resolved photoemission spectroscopy (TRARPES) study of WSe2, a layered semiconductor of interest for valley electronics. The results for below-gap optical pumping reveal energy-gain and -loss Floquet replica valence bands that appear instantaneously in concert with the pump pulse. Energy shift, broadening, and complex intensity variation and oscillation at twice the phonon frequency for the valence bands are observed at time scales ranging from the femtosecond to the picosecond and beyond. Furthermore, the underlying physics is rich, including ponderomotive interaction, dressing of the electronic states, creation of coherent phonon pairs, and diffusion of charge carriers – effects operating at vastly different time domains.},

  doi          = {10.1038/s41598-017-16076-z},

  journal      = {Scientific Reports},

  number       = 1,

  volume       = 7,

  place        = {United States},

  year         = {2017},

  month        = {11}

}

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https://doi.org/10.1038/s41598-017-16076-z

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Cited by: 8 works

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Figure 1: Crystal structure, Brillouin zone, and electronic structure of WSe₂. (a) Top and side views of the atomic structure of 2H-WSe₂. (b) First Brillouin zone and its planar projection. (c) X-ray photoemission spectroscopy data taken from a cleaved WSe₂ crystal using 1200-eV photons. (d) Bulk band structure obtained bymore »

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Works referenced in this record:

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Works referencing / citing this record:

Ab Initio Simulation of Attosecond Transient Absorption Spectroscopy in Two-Dimensional Materials
journal, September 2018

Sato, Shunsuke; Hübener, Hannes; De Giovannini, Umberto
Applied Sciences, Vol. 8, Issue 10
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Title: Femtosecond to picosecond transient effects in WSe2 observed by pump-probe angle-resolved photoemission spectroscopy

Abstract

Citation Formats

Figures / Tables:

Valley-dependent optoelectronics from inversion symmetry breaking journal, June 2008

Theory of Floquet band formation and local pseudospin textures in pump-probe photoemission of graphene journal, May 2015

Optical properties of mixed transition metal dichalcogenide crystals journal, December 1989

Probing Unfolded Acoustic Phonons with X Rays journal, July 2008

Laser-assisted photoemission from surfaces journal, February 2008

Observation of Floquet-Bloch States on the Surface of a Topological Insulator journal, October 2013

Theoretical study of thermoelectric properties of few-layer MoS2 and WSe2 journal, January 2014

All-optical materials design of chiral edge modes in transition-metal dichalcogenides journal, October 2016

Floquet topological insulator in semiconductor quantum wells journal, March 2011

Monitoring Electron-Photon Dressing in WSe 2 journal, November 2016

Hidden spin polarization in inversion-symmetric bulk crystals journal, April 2014

Coherent Lattice Vibrations in Mono- and Few-Layer WSe 2 journal, April 2016

Femtosecond core-level photoemision spectroscopy on 1 T -TaS 2 using a 60-eV laser source journal, February 2011

The band structures of some transition metal dichalcogenides. III. Group VIA: trigonal prism materials journal, April 1972

Direct observation of spin-polarized bulk bands in an inversion-symmetric semiconductor journal, October 2014

Direct Observation of Multiphoton Processes in Laser-Induced Free-Free Transitions journal, August 1977

Valley-selective optical Stark effect in monolayer WS2 journal, December 2014

Optical response of graphene under intense terahertz fields journal, June 2011

Coherent Lattice Vibrations in Mono- and Few-Layer WSe 2 journal, April 2016

Theoretical study of thermoelectric properties of few-layer MoS2 and WSe2 journal, January 2014

Electronic structures and theoretical modelling of two-dimensional group-VIB transition metal dichalcogenides journal, January 2015

The band structures of some transition metal dichalcogenides. III. Group VIA: trigonal prism materials journal, April 1972

Surface photovoltage effect at the p -WSe 2 :Rb surface: Photoemission experiment and numerical model journal, February 2011

Observation of Floquet-Bloch states on the surface of a topological insulator text, January 2013

Theory of pump-probe photoemission in graphene: Ultrafast tuning of Floquet bands and local pseudospin textures text, January 2014

Hidden spin polarization in inversion-symmetric bulk crystals text, January 2014

Direct observation of spin-polarised bulk bands in an inversion-symmetric semiconductor text, January 2014

Generation and evolution of spin-, valley- and layer-polarized excited carriers in inversion-symmetric WSe2 text, January 2016

Ab Initio Simulation of Attosecond Transient Absorption Spectroscopy in Two-Dimensional Materials journal, September 2018

Title: Femtosecond to picosecond transient effects in WSe₂ observed by pump-probe angle-resolved photoemission spectroscopy

Valley-dependent optoelectronics from inversion symmetry breaking
journal, June 2008

Theory of Floquet band formation and local pseudospin textures in pump-probe photoemission of graphene
journal, May 2015

Optical properties of mixed transition metal dichalcogenide crystals
journal, December 1989

Probing Unfolded Acoustic Phonons with X Rays
journal, July 2008

Laser-assisted photoemission from surfaces
journal, February 2008

Observation of Floquet-Bloch States on the Surface of a Topological Insulator
journal, October 2013

Theoretical study of thermoelectric properties of few-layer MoS2 and WSe2
journal, January 2014

All-optical materials design of chiral edge modes in transition-metal dichalcogenides
journal, October 2016

Floquet topological insulator in semiconductor quantum wells
journal, March 2011

Monitoring Electron-Photon Dressing in WSe ₂
journal, November 2016

Hidden spin polarization in inversion-symmetric bulk crystals
journal, April 2014

Coherent Lattice Vibrations in Mono- and Few-Layer WSe ₂
journal, April 2016

Femtosecond core-level photoemision spectroscopy on $1 T$ -TaS $_{2}$ using a 60-eV laser source
journal, February 2011

The band structures of some transition metal dichalcogenides. III. Group VIA: trigonal prism materials
journal, April 1972

Direct observation of spin-polarized bulk bands in an inversion-symmetric semiconductor
journal, October 2014

Direct Observation of Multiphoton Processes in Laser-Induced Free-Free Transitions
journal, August 1977

Valley-selective optical Stark effect in monolayer WS2
journal, December 2014

Optical response of graphene under intense terahertz fields
journal, June 2011

Coherent Lattice Vibrations in Mono- and Few-Layer WSe ₂
journal, April 2016

Theoretical study of thermoelectric properties of few-layer MoS2 and WSe2
journal, January 2014

Electronic structures and theoretical modelling of two-dimensional group-VIB transition metal dichalcogenides
journal, January 2015

The band structures of some transition metal dichalcogenides. III. Group VIA: trigonal prism materials
journal, April 1972

Surface photovoltage effect at the $p$ -WSe $_{2}$ :Rb surface: Photoemission experiment and numerical model
journal, February 2011

Observation of Floquet-Bloch states on the surface of a topological insulator
text, January 2013

Theory of pump-probe photoemission in graphene: Ultrafast tuning of Floquet bands and local pseudospin textures
text, January 2014

Hidden spin polarization in inversion-symmetric bulk crystals
text, January 2014

Direct observation of spin-polarised bulk bands in an inversion-symmetric semiconductor
text, January 2014

Generation and evolution of spin-, valley- and layer-polarized excited carriers in inversion-symmetric WSe2
text, January 2016

Ab Initio Simulation of Attosecond Transient Absorption Spectroscopy in Two-Dimensional Materials
journal, September 2018