Open positions for PhD/MSc students and Postdoctoral fellows

in Experimental Study of

Ultrafast Dynamics of Many-Body Quantum Systems

Over the past fifteen years, Miner’s research group at UBC has been working on laser-driven ultrafast coherent control of molecular dynamics, specifically – the control of molecular rotation with a unique laser system known as an “optical centrifuge”. Molecular “super-rotors”, i.e. molecules spun by the centrifuge to extreme rotational states, exhibit a number of unusual properties. From extremely long rotational coherence, to rotation-induced magnetic fields and mechanical Faraday effect – these phenomena were studied in our lab for the first time, thanks to the powerful tool of the optical centrifuge and other advanced experimental techniques, such as femtosecond pulse shaping, velocity map ion imaging and coherent Raman spectroscopy.

Taking advantage of our expertise in rotational control of quantum objects with laser light, we have been expanding our research into strongly interacting dense many-body quantum systems, such as superfluid helium. In his famous experiment more than 70 years ago, Andronikashvili has observed superfluidity on a macroscopic scale by immersing in liquid helium a mechanically controlled rotating top. Similar studies at the atomic level proved impossible due to the lack of controllable nano-scale rotors. Our ability to spin molecules in a controlled way using ultrashort laser pulses offer a unique opportunity to probe microscopic superfluidity with molecular rotors. We are actively pursuing this goal in two quantum systems: superfluid helium nanodroplets and bulk superfluid helium (https://www.science.org/doi/10.1126/sciadv.adi2455 ).

Besides molecules embedded in superfluid helium, the latter is “full” of quasiparticles (or collective quantum excitations of the liquid), known as rotons and responsible for its superfluid properties. We have recently discovered that femtosecond laser pulses can be used to both excite and detect rotons in the superfluid (https://www.pnas.org/doi/10.1073/pnas.2303231120 ). This discovery opens a new window into studying the dynamics of superfluid helium on femto- and picosecond time scales, which until now have never been explored, providing new information on the microscopic mechanisms of superfluidity.

We are looking for graduate students and postdocs interested in joining our team in this exciting pursuit of laser-controlled dynamics in the many-body quantum system of superfluid helium.