Programme

P.55 -- Poster, VCTP-45

Date: Tuesday, 13 October 2020

Time: 08:30 - 10:00

Probing degrees of orientation of polar molecules

Kim-Ngan Nguyen-Huynh (1), Ngoc-Loan Phan (1), Cam-Tu Le (2), Dinh-Duy T. Vu (2) and Van-Hoang Le (1)

(1) Ho Chi Minh City University of Education, Ho Chi Minh City, Vietnam; (2) Ton Duc Thang University, Ho Chi Minh City, Vietnam

Determining the degrees of orientation of molecular sample is an important issue since it affects the outcomes of the chemical reactions and physical interactions. In experiment, there are different ways to directly measure the degrees of orientation, such as using a terahertz pulse [1], or two-color fields [2]. However, these methods using strong electric field thus leading to the destroying molecules [1, 2]. Recently, some nondestructive methods adopting high-order harmonic generation (HHG), resulted in the interaction between molecules and ultrashort, intense laser, are proposed to probe the orientation of polar molecular [3–6]. However, these methods are only validated when appropriate laser pulses are used. Moreover, the method can probe only the absolute value, but not the sign of the degrees of orientation. In this report, we present a comprehensive method to probe the full-range degrees of orientation of a sample of CO molecule using HHG. The method can be applied regardless of the laser shape and laser parameters. The method is performed by adopting the time-frequency profile of HHG. We found that, with an arbitrary laser pulse, the time-profile of a harmonic order strongly depends on the degrees of orientation. The method is highly reliable with considerably small errors. REFERENCES [1] J. H. Mun, H. Sakai, and R. González-Férez, Phys. Rev. A 99, 1 (2019). [2] P. Babilotte, K. Hamraoui, F. Billard, E. Hertz, B. Lavorel, O. Faucher, and D. Sugny, Phys. Rev. A 94, 1 (2016). [3] E. Frumker, C. T. Hebeisen, N. Kajumba, J. B. Bertrand, H. J. Wörner, M. Spanner, D. M. Villeneuve, A. Naumov, and P. B. Corkum, Phys. Rev. Lett. 109, 113901(5) (2012). [4] G. Frumker, Eugene and Kajumba, N and Bertrand, JB and Worner, Hans Jakob and Hebeisen, CT and Hockett, P and Spanner, Michael and Patchkovskii, Serguei and Paulus and D. Villeneuve, Phys.Rev. Lett 233904, 233904(5) (2012). [5] Y. Z. Shi, B. Zhang, W. Y. Li, S. J. Yu, and Y. J. Chen, Phys. Rev. A 95, 1 (2017). [6] W. Y. Li, R. H. Xu, X. J. Xie, and Y. J. Chen, Phys. Rev. A 100, 1 (2019).

Presenter: Nguyen Huynh Kim Ngan

Presentation file: