Programme

O.17 -- Oral, VCTP-47

Date: Thursday, 4 August 2022

Time: 16:25 - 16:50

Generation of dynamic stark-induced degenerate vibronic state by two shift up non-resonant lasers

Quang Huy Ho (1), Ngoc Loan Phan (1), Yuichi Fujimura (2), and Hirobumi Mineo (3)

(1) Department of Physics, Ho Chi Minh City University of Education, 280 An Duong Vuong Str., 5 Dist., Ho Chi Minh City, Viet Nam. (2) Department of Chemistry, Graduate School of Science, Tohoku University, 6-3, Aramaki Aza-Aoba, Aoba-ku, Sendai 980-8578 Japan. (3) Science and Technology Advanced Institute (STAI), Van Lang University 69/68 Dang Thuy Tram Str., Binh Thanh Dist., Ho Chi Minh City, Viet Nam.

In the past it was commonly understood that the coherent π-electron rotation could not be generated in low symmetry aromatic ring molecules, which have no degenerate electronic excited state. Recently we demonstrated by that the unidirectional π-electron rotation can be created even in low symmetry aromatic ring molecules using the two linearly polarized lasers with a relative phase [1]. The key point is to create a degenerate electronic state of two quasi-degenerate electronic excited states by applying two non-resonant lasers. Here, vibrational degrees of freedom were not taken into account. In our recent work [2] we have taken into account the nuclear vibrational effects on the unidirectional π-electron rotation in the adiabatic approximation, where a weak coupling model of two electronic states with a few vibrational states is adopted [2], where the two lowest vibronic states in two electronic excited states were set to be degenerate by two lasers (Dynamic Stark induced-Degenerate vibronic state-DSIDVS). Here vibrational states in the electronic excited state 1 are shifted up by the laser a, and the lowest vibrational state in the electronic excited state 2 is shifted down by the laser b, whereas the other vibrational states in the electronic excited state 2 are shifted up by the laser b. Such opposite behaviours in the level shift of the vibronic states in the electronic excited state 2 make it complicate to describe the behaviours of dynamic Stark-induced vibronic states. In this work we propose an alternative method using the two non-resonant shift-up lasers to avoid the complication mentioned above. [1] H. Mineo, M. Yamaki, G.S. Kim, Y. Teranishi, and Y. Fujimura, Phys. Chem. Chem. Phys. 18, 26786-26795 (2016). [2] H. Mineo, N.L. Phan, D.K. La and Y. Fujimura, J. Phys. Chem. A 125, 1476-1489 (2021).

Presenter: Ho Quang Huy