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Phase Control of Wave Packet Dynamics Using Shape Femtosecond Pulses



R Uberna, Z Amitay, R A. Loomis, S R. Leone


Coherent vibrational and rotational dynamics of the Li2 molecule is controlled by varying the relative phases, φn, of the rovibrational wave packet components, /n>ei(ωnt+φn). The coherent superposition is created by excitation of a set of ten rovibronic E1ςg+ (VE = 12=16, JE = 17, 19) states from an intermediate state, A1ςu+A = 14, JA = 18), using ultrashort optical pulses with well-defined spectral amplitudes and phasesencoded into the pulse by a liquid crystal spatial light modulator. The wave packet is probed by time-dependent photoionization and the quantum interference signal is measured as a total ionization yield. The phases of the wave packet components are optimized to produce partial localization of the wave packet at a given time t, in specific regions of three dimensional space defined by the radial and angular coordinates. As a result, the ionization yield, I(t), is maximized or minimized at a time t. The degree of control achieved in the experiment is (Imax - I min) /Imax = 64 ( 8)%. The experimental data are interpreted in terms of time-dependent radial and angular probability distributions, calculated for different initial conditions that are determined by the phase relationships in the excitation pulse.
Faraday Discussions


femtosecond laser, phase control, wave packet


Uberna, R. , Amitay, Z. , Loomis, R. and Leone, S. (2021), Phase Control of Wave Packet Dynamics Using Shape Femtosecond Pulses, Faraday Discussions (Accessed June 24, 2024)


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Created October 12, 2021