Welcome to the website of the Slovenian cold atom lab. We use an ultracold quantum gas of cesium to explore matter waves and to develop quantum devices.
BEC is a state of coupled bosonic atoms at a temperature near absolute zero. Under these conditions, a large fraction of the atoms occupy the lowest quantum state, while the quantum nature of atoms is manifested in the form of superfluidity. The superfluidity is a macroscopic phenomenon where the material behaves as a quantum fluid that flows without viscosity and is analogous to the phenomenon of superconductivity in solids. Because of this analogy the BEC can be used as a quantum simulator of solid state physics, e.g., to study superconductivity and, in more general, to explore the physics of strongly correlated electrons.
Recent highlights
- Single-shot measurement of magnetic gradients with cold cesium atomsA novel method for detecting the gradient of a magnetic field uses an elongated cloud of cesium atoms cooled near the absolute zero. Since the rotation of atomic spins depends on the magnetic field, an image of the spin states can be used to measure how the magnetic field changes along the cloud. The gradient is determined from a single image, which is an advantage over standard methods where multiple images are needed.
- Emission of correlated jets from a driven matter-wave soliton in a quasi-one-dimensional geometryWe recently published an article on jet emission in Physical Review A. In the paper we demonstrate the emission of correlated atom jets from a matter-wave soliton in a quasi-one-dimensional optical trap. We characterize the dependence of jet properties on the frequency, amplitude and length of the modulation, and qualitatively reproduce the trends in the…
Using lasers and magnetooptical trap the cesium atoms in the ultrahigh vacuum are first slowed down and caught, and thus cooled to the temperature range of several hundred μK. In the next step, by means of Raman transitions, the cesium atoms end up in one of the well-defined low-lying energy states and the temperature falls below 1 μK. At the same time the atoms are caught in the so-called optical trap by a set of extremely powerful laser beams. The atoms are further cooled by evaporation, which lowers the temperature to the range of nK, which is low enough for the atoms to condense.

Selected Publications
Single-shot Stern-Gerlach magnetic gradiometer with an expanding cloud of cold cesium atoms
Katja Gosar, Tina Arh, Tadej Mežnaršič, Ivan Kvasič, Dušan Ponikvar, Tomaž Apih, Rainer Kaltenbaek, Rok Žitko, Erik Zupanič, Samo Beguš, and Peter Jeglič Phys. Rev. A 103, 022611 (2021), arXiv:2011.09779 |
Emission of correlated jets from a driven matter-wave soliton in a quasi-one-dimensional geometry Tadej Mežnaršič, Rok Žitko, Tina Arh, Katja Gosar, Erik Zupanič, and Peter Jeglič Phys. Rev. A 101, 031601(R) (2020), arXiv:1905.10286 |
Cesium bright matter-wave solitons and soliton trains Tadej Mežnaršič, Tina Arh, Jure Brence, Jaka Pišljar, Katja Gosar, Žiga Gosar, Rok Žitko, Erik Zupanič, and Peter Jeglič Phys. Rev. A 99, 033625 (2019), arXiv:1902.03144 |
Ongoing Projects
Development of building blocks for new European quantum communication network
High-resolution optical magnetometry with cold cesium atoms
Quantum Technologies with Ultra-Cold Atoms
Latest news
- Cold Atoms in Space: Community Workshop Summary & Roadmap“Cold Atoms in Space: Community Workshop Summary & Roadmap” is now available on arXiv.
- Congratulations to Katja Gosar on her recent successful defense of her Masters thesis!Congratulations to Katja Gosar on her recent successful defense of her Masters thesis The use of optical tweezers in experiments with cold atoms and Bose-Einstein condensate.