Strongly driven quantum pendulum of a polar molecule

The behavior of molecules subject to strong laser fields has been arapidly growing topic in molecular physics and chemistry during thelast years. The anisotropic interaction between an isolated moleculeand a nonresonant, linearly polarized laser field creates pendular states,i. e., directional superpositions of field-free rotational states [1]. Wedisentangled the rotational and pendular state wavepacket dynamicsof quantum state selected carbonyl sulfide (OCS) molecules. A strongoscillation on the degree of alignment is observed that resembles themotion of a classical pendulum. Features in the transition from impulsive,non-adiabatic to adiabatic alignment and orientation were disentangled,with implications on the switching behavior of fast molecularswitches in non dissipative media. In addition, we demonstrated howthe combination of quantum state selection and rotational coherencespectroscopy allows for a complete measurement of magnitude and polarizationof angular momenta of molecules in field-free space.[1] B. Friedrich and D. Herschbach, Phys. Rev. Lett. 74, 4623 (1995)Part: M