TY - JOUR
T1 - Ultrafast optical absorption and coherent phonon generation in monolayer and bilayer transition metal dichalcogenides
AU - Cahaya, A. B.
AU - Majidi, M. A.
N1 - Funding Information:
We acknowledge financial support from the Ministry of Research and Technology of the Republic of Indonesia through PDUPT Research Grant No NKB-218/UN2.RST/HKP.05.00/2020.
Publisher Copyright:
© Published under licence by IOP Publishing Ltd.
PY - 2021/3/8
Y1 - 2021/3/8
N2 - When ultrashort laser pulses are applied to the solid-state material within a time scale less than the period of a particular phonon mode, the energy and momentum of the absorbed light are used by photo-excited carriers to interact collectively with the crystal lattices and generate lattice oscillations coherently, known as the coherent phonons. The Fourier transform of the absorption modulation due to the coherent phonon oscillations gives the coherent phonon intensity. In this work, we theoretically investigate the shape of coherent phonon intensity for transition metal dichalcogenides as a function of the polarization angle of the laser pulses. In particular, we focus on the E2g and A1g phonons in monolayer and bilayer molybdenum disulfides. Within the simplified theory of displacive excitation of coherent phonons, we find that the laser pulses uniquely select the electronic states in monolayer and bilayer molybdenum disulfides, resulting in a rich feature of the polar plots of the energy-dependent coherent phonon intensity of these materials.
AB - When ultrashort laser pulses are applied to the solid-state material within a time scale less than the period of a particular phonon mode, the energy and momentum of the absorbed light are used by photo-excited carriers to interact collectively with the crystal lattices and generate lattice oscillations coherently, known as the coherent phonons. The Fourier transform of the absorption modulation due to the coherent phonon oscillations gives the coherent phonon intensity. In this work, we theoretically investigate the shape of coherent phonon intensity for transition metal dichalcogenides as a function of the polarization angle of the laser pulses. In particular, we focus on the E2g and A1g phonons in monolayer and bilayer molybdenum disulfides. Within the simplified theory of displacive excitation of coherent phonons, we find that the laser pulses uniquely select the electronic states in monolayer and bilayer molybdenum disulfides, resulting in a rich feature of the polar plots of the energy-dependent coherent phonon intensity of these materials.
UR - http://www.scopus.com/inward/record.url?scp=85103124446&partnerID=8YFLogxK
U2 - 10.1088/1742-6596/1816/1/012052
DO - 10.1088/1742-6596/1816/1/012052
M3 - Conference article
AN - SCOPUS:85103124446
SN - 1742-6588
VL - 1816
JO - Journal of Physics: Conference Series
JF - Journal of Physics: Conference Series
IS - 1
M1 - 012052
T2 - 10th International Conference on Theoretical and Applied Physics, ICTAP 2020
Y2 - 20 November 2020 through 22 November 2020
ER -