Report

Teaser, summary, work performed and final results

Periodic Reporting for period 1 - SYMULGAS (Synthetic magnetism with ultracold Fermi gases of strontium)

Teaser

Ultracold atoms can provide a unique perspective into the quantum world. Quantum degenerate gases at nanokelvin temperatures are being created in our laboratory during this fellowship with the goal to explore a new frontier of physics called topological states of matter...

Summary

Ultracold atoms can provide a unique perspective into the quantum world. Quantum degenerate gases at nanokelvin temperatures are being created in our laboratory during this fellowship with the goal to explore a new frontier of physics called topological states of matter. Topological phenomena emerge when the geometry of a system dominates its behavior and the exact rates of interaction are of little significance. The Nobel Prize for Physics 2016 has been awarded for “theoretical discoveries of topological phase transitions and topological phases of matter”.
The initial goal of my project was to get the opportunity to work in establishing ultracold strontium (Sr) as a powerful experimental platform to shed light on outstanding problems of magnetism of quantum matter in periodic potentials. As a side-benefit probing fermionic strontium in optical lattices with ultra-narrow lasers can reveal properties useful for the improvement of atomic lattice clocks that currently are the most accurate time-keepers in the world. Our work has the potential to impact other disciplines such as condensed matter and optics.

This project is only possible and realistic since the host group of F. Schreck at the University of Amsterdam (UvA) - the first group in the world to make a Sr BEC and the only one in Europe with such expertise - has a fully operational apparatus which produces quantum degenerate gases of strontium. Exciting developments in the front of ultracold heteronuclear molecules made this apparatus inaccessible to my project at a full-time basis and we took the initiative to build a completely new experiment with the same aforementioned goals that we have finished within the duration of that action.

Work performed

In the view of the aforementioned strategic decision and towards the goal of establishing strontium as a powerful and versatile platform for experimentally exploring artificial magnetic fields in optical potentials we have taken action in four directions.
• We designed and built a new, versatile, and extendable apparatus where experiments on strontium quantum gases and strontium mixtures with other atoms can be performed. By the moment of writing this report we can create quantum degenerate gases of strontium.
• We devised schemes for optical microscopy at the single-atom level (mention the specs and the cooling protocol).
• We created the laser toolbox to explore topological physics (mention the lasers)
• We have theoretically explored precise ways of performing experiments with artificial gauge fields in the upcoming months. (mention the scheme)
In the course of that action I have supervised 5 Bachelor’s students for short projects (auto-locking of kHz lasers, tunable lenses for optical transport, 689 nm laser system for narrowline laser cooling), 2 Master students (compensation coils for a month project, creation of red MOT and development of clock lasers), 2 PhD students.
For the dissemination of our results during this action we have:
• Attended 1 international workshop on artificial gauge fields (Dresden, Germany, 2015)
• Attended with posters in 5 Dutch conferences (Lunteren (2015,2016, and 2017) for AMO physics, Veldhoven (2016, 2017) Physics)
• Institute of Physics seminar (presented by PhD student Oleksiy Onischenko)
• 2 presentations for the UvA Quantum Gases Group and the university Technology Center
• Lab tours and demonstrations for kids, college students and the general public.

Final results

My project is now completed and there are a number of research directions that can be followed because of this action. Because of my fellowship it is financially possible to extend my contract with the University of Amsterdam and the Group of Florian Schreck for another year were all the effort can be brought to fruition. In addition, our team will be increased by two more members. A masters’ graduate (Alex Ulrech) from our lab decided to continue on the artificial gauge fields project starting the 1st of October and a new masters’ student joined already (started the 1st of September) our team to realize the transport of cold-atoms and the single-atom, single-site microscope objective that I have designed.
In the upcoming weeks we will be obtaining a quantum degenerate gas of fermionic strontium (the second one in Europe and the second in our Group establishing thus University of Amsterdam as a powerhouse on strontium Fermi gases). Immediately after we will set-up the toolbox towards a novel way to realize optical flux lattices with alkaline-earth elements. More specifically spin distillation of strontium and realize nuclear-spin dependent imaging in the form of optical Stern-Gerlach separation and perform Raman coupling of nuclear spins using the narrow 3P1 transition.
We are already building the set-up for the creation of optical flux lattices with lifetimes of the order of 100 ms – a long sought goal for the field of ultracold quantum gases. We believe that the perfection of the clock lasers can in the future increase the lifetime of a system that supports optical flux lattices to the order of seconds.
The completion of a Hz-level laser system can be enable us to realize one of the gedanken experiments of the Nobel laureate related to a spin-pumping mechanism related to the fractional quantum Hall effect.
The creation of a new apparatus for quantum simulation with Fermi gases lead to the integration of our lab into the newly formed QuSoft collaboration at the University of Amsterdam with the goal of pushing forward towards quantum computing where our lab will contribute to the implementation of quantum algorithms by providing nuclear-spin based logical gates.
This action also gave me the opportunity to offer my expertise beyond the immediate needs of our laboratory. In these two years I served as:
• Program committee member for the OPTICS conference ICET in Portugal (2016, 2017)
• Reviewer for Scientific Reports, Science Advances, Journal of Physics Communications

Website & more info

More info: http://www.strontiumbec.com.