Control and study of molecular dynamics in many-body quantum systems

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My research is focused on controlling molecular dynamics with laser pulses, whose intensity, phase and polarization are tailored so as to make the molecule rotate in a desired way. In recent years, my group has developed methods of controlling molecular rotation with such laser instruments as an "optical centrifuge" and a "chiral pulse train". We have since used them to study new and exotic molecular objects, known as "molecular super-rotors". Super-rotors are ultrafast rotating molecules whose synchronous uni-directional rotation is controlled by the laser field. Our centrifuge is one of three in the world (two until 2017) and the only one in Canada. It is also the only centrifuge worldwide in which the three fundamental parameters of molecular "super-rotation" - its frequency, directionality and phase - can be measured directly. This unique tool enabled us to perform a number of pioneering molecular studies, impossible in any other research laboratory. Until now, we have investigated the properties of isolated molecular super-rotors and their collisional properties within thermal molecular ensembles, where quantum correlations and many-body physics are of little importance. In the next few years, I will expand this research to studying rotational dynamics of molecules embedded in quantum media. We will investigate coherent molecular rotation inside three types of quantum environment: (1) the macroscopic bath of superfluid liquid helium; (2) its small nanoscale realization in the form of a helium nanodroplet containing a few thousand helium atoms; and (3) an even smaller cluster of up to a few tens of helium atoms. Molecular rotors, whose spatial orientation and coherent rotational dynamics will be accurately controlled with our shaped laser pulses, will be used as local nano-probes of these correlated quantum media. We will study the appearance and the manifestation of superfluidity at different length scales by monitoring and characterizing the rotation of an embedded molecule, as well as the response of the medium to that rotation. Owing to the unique properties of isolated molecular super-rotors, found in our recent works, I anticipate many interesting discoveries from bringing these exotic molecular objects in direct contact with many-body quantum systems, e.g. a superfluid. Understanding complex quantum media, in which the motion of an individual molecule becomes entangled with the dynamics of the surrounding atoms and molecules through a collective many-body quantum state, is key to the progress in emerging quantum technologies, which are expected to revolutionize secure communications, computer analysis of biological systems, and sensing of small changes in electrical, magnetic and gravitational fields. An exposure to the state-of-the-art laser technology, such as an optical centrifuge, ensures that my students will have an unmatched training opportunity which will prepare them for careers either in academic or industrial sector.