Abstract
The atomic and electronic dynamics in the topological insulator (TI) Bi2Te3 under strong photoexcitation were characterized with time-resolved electron diffraction and time-resolved mid-infrared spectroscopy. Three-dimensional TIs characterized as bulk insulators with an electronic conduction surface band have shown a variety of exotic responses in terms of electronic transport when observed under conditions of applied pressure, magnetic field, or circularly polarized light. However, the atomic motions and their correlation between electronic systems in TIs under strong photoexcitation have not been explored. The artificial and transient modification of the electronic structures in TIs via photoinduced atomic motions represents a novel mechanism for providing a comparable level of bandgap control. The results of time-domain crystallography indicate that photoexcitation induces two-step atomic motions: first bismuth and then tellurium center-symmetric displacements. These atomic motions in Bi2Te3 trigger 10% bulk bandgap narrowing, which is consistent with the time-resolved mid-infrared spectroscopy results.
| Original language | English |
|---|---|
| Article number | 024504 |
| Journal | Journal of Chemical Physics |
| Volume | 145 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - Jul 14 2016 |
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ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry
Cite this
Bandgap modulation in photoexcited topological insulator Bi2Te3 via atomic displacements. / Hada, Masaki; Norimatsu, Katsura; Tanaka, Sei′ichi; Keskin, Sercan; Tsuruta, Tetsuya; Igarashi, Kyushiro; Ishikawa, Tadahiko; Kayanuma, Yosuke; Miller, R. J Dwayne; Onda, Ken; Sasagawa, Takao; Koshihara, Shin Ya; Nakamura, Kazutaka G.
In: Journal of Chemical Physics, Vol. 145, No. 2, 024504, 14.07.2016.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Bandgap modulation in photoexcited topological insulator Bi2Te3 via atomic displacements
AU - Hada, Masaki
AU - Norimatsu, Katsura
AU - Tanaka, Sei′ichi
AU - Keskin, Sercan
AU - Tsuruta, Tetsuya
AU - Igarashi, Kyushiro
AU - Ishikawa, Tadahiko
AU - Kayanuma, Yosuke
AU - Miller, R. J Dwayne
AU - Onda, Ken
AU - Sasagawa, Takao
AU - Koshihara, Shin Ya
AU - Nakamura, Kazutaka G.
PY - 2016/7/14
Y1 - 2016/7/14
N2 - The atomic and electronic dynamics in the topological insulator (TI) Bi2Te3 under strong photoexcitation were characterized with time-resolved electron diffraction and time-resolved mid-infrared spectroscopy. Three-dimensional TIs characterized as bulk insulators with an electronic conduction surface band have shown a variety of exotic responses in terms of electronic transport when observed under conditions of applied pressure, magnetic field, or circularly polarized light. However, the atomic motions and their correlation between electronic systems in TIs under strong photoexcitation have not been explored. The artificial and transient modification of the electronic structures in TIs via photoinduced atomic motions represents a novel mechanism for providing a comparable level of bandgap control. The results of time-domain crystallography indicate that photoexcitation induces two-step atomic motions: first bismuth and then tellurium center-symmetric displacements. These atomic motions in Bi2Te3 trigger 10% bulk bandgap narrowing, which is consistent with the time-resolved mid-infrared spectroscopy results.
AB - The atomic and electronic dynamics in the topological insulator (TI) Bi2Te3 under strong photoexcitation were characterized with time-resolved electron diffraction and time-resolved mid-infrared spectroscopy. Three-dimensional TIs characterized as bulk insulators with an electronic conduction surface band have shown a variety of exotic responses in terms of electronic transport when observed under conditions of applied pressure, magnetic field, or circularly polarized light. However, the atomic motions and their correlation between electronic systems in TIs under strong photoexcitation have not been explored. The artificial and transient modification of the electronic structures in TIs via photoinduced atomic motions represents a novel mechanism for providing a comparable level of bandgap control. The results of time-domain crystallography indicate that photoexcitation induces two-step atomic motions: first bismuth and then tellurium center-symmetric displacements. These atomic motions in Bi2Te3 trigger 10% bulk bandgap narrowing, which is consistent with the time-resolved mid-infrared spectroscopy results.
UR - http://www.scopus.com/inward/record.url?scp=84978468824&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84978468824&partnerID=8YFLogxK
U2 - 10.1063/1.4955188
DO - 10.1063/1.4955188
M3 - Article
AN - SCOPUS:84978468824
VL - 145
JO - Journal of Chemical Physics
JF - Journal of Chemical Physics
SN - 0021-9606
IS - 2
M1 - 024504
ER -