Karamatskos Evangelos T, Raabe Sebastian, Mullins Terry, Trabattoni Andrea, Stammer Philipp, Goldsztejn Gildas, Johansen Rasmus R, Długołecki Karol, Stapelfeldt Henrik, Vrakking Marc J J, Trippel Sebastian, Rouzée Arnaud, Küpper Jochen
Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607, Hamburg, Germany.
Department of Physics, Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany.
Nat Commun. 2019 Jul 29;10(1):3364. doi: 10.1038/s41467-019-11122-y.
Recording molecular movies on ultrafast timescales has been a longstanding goal for unravelling detailed information about molecular dynamics. Here we present the direct experimental recording of very-high-resolution and -fidelity molecular movies over more than one-and-a-half periods of the laser-induced rotational dynamics of carbonylsulfide (OCS) molecules. Utilising the combination of single quantum-state selection and an optimised two-pulse sequence to create a tailored rotational wavepacket, an unprecedented degree of field-free alignment, 〈cosθ〉 = 0.96 (〈cosθ〉 = 0.94) is achieved, exceeding the theoretical limit for single-pulse alignment. The very rich experimentally observed quantum dynamics is fully recovered by the angular probability distribution obtained from solutions of the time-dependent Schrödinger equation with parameters refined against the experiment. The populations and phases of rotational states in the retrieved time-dependent three-dimensional wavepacket rationalises the observed very high degree of alignment.
在超快时间尺度上记录分子电影一直是揭示分子动力学详细信息的长期目标。在此，我们展示了对羰基硫（OCS）分子激光诱导旋转动力学超过一个半周期的超高分辨率和高保真度分子电影的直接实验记录。利用单量子态选择和优化的双脉冲序列相结合来创建定制的旋转波包，实现了前所未有的无场取向度，〈cosθ〉 = 0.96（〈cosθ〉 = 0.94），超过了单脉冲取向的理论极限。通过从含时薛定谔方程解中获得的角概率分布，并根据实验对参数进行优化，完全恢复了实验中观测到的非常丰富的量子动力学。检索到的含时三维波包中旋转态的布居和相位解释了观测到的非常高的取向度。
