Ultracold <sup>6</sup>Li-<sup>53</sup>Cr Fermi mixtures with tunable interactions
ORAL
Abstract
Mass-imbalanced Fermi mixtures are expected to greatly enhance the observability of elusive regimes of highly-correlated fermionic matter, primarily in the context of unconventional superfluidity and quantum magnetism.
Here, we report on our progress towards novel 6Li-53Cr degenerate Fermi mixtures. The peculiar mass ratio of our system uniquely enables the existence of resonant few-body cluster states with p-wave symmetry on the molecular side of an inter-species Feshbach resonance, together with an extraordinary suppression of three-body recombination processes at strong repulsion. These properties will allow us to resonantly tune elastic few-body p-wave interactions on top of the standard 2-body ones, as well as to overcome pairing instabilities in repulsive Fermi mixtures.
First, we will discuss our all-optical strategy to attain large ultracold samples of up to 106 Li and 3 105 Cr atoms at micro-Kelvin temperatures. Second, we will report on extensive Feshbach spectroscopy performed onto the six Li-Cr spin-mixtures of lowest energy. In particular, we identified more than 30 inter-species resonances, including four isolated features in the absolute mixture ground state, immune to two-body losses, and thereby promising for future many-body surveys.
[1] E. Neri et al., Phys. Rev. A 101, 063602 (2020)
[2] B. Bazak and D. S. Petrov, Phys. Rev. Lett. 118, 083002
[3] D. S. Petrov, Phys. Rev. A 67, 010703(R)
Here, we report on our progress towards novel 6Li-53Cr degenerate Fermi mixtures. The peculiar mass ratio of our system uniquely enables the existence of resonant few-body cluster states with p-wave symmetry on the molecular side of an inter-species Feshbach resonance, together with an extraordinary suppression of three-body recombination processes at strong repulsion. These properties will allow us to resonantly tune elastic few-body p-wave interactions on top of the standard 2-body ones, as well as to overcome pairing instabilities in repulsive Fermi mixtures.
First, we will discuss our all-optical strategy to attain large ultracold samples of up to 106 Li and 3 105 Cr atoms at micro-Kelvin temperatures. Second, we will report on extensive Feshbach spectroscopy performed onto the six Li-Cr spin-mixtures of lowest energy. In particular, we identified more than 30 inter-species resonances, including four isolated features in the absolute mixture ground state, immune to two-body losses, and thereby promising for future many-body surveys.
[1] E. Neri et al., Phys. Rev. A 101, 063602 (2020)
[2] B. Bazak and D. S. Petrov, Phys. Rev. Lett. 118, 083002
[3] D. S. Petrov, Phys. Rev. A 67, 010703(R)
*This work was supported by the ERC through grant No. 637738 PoLiChroM, by the Italian MIUR through the FARE Grant No. R168HMHFYM, and by the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 894442.
–
Publication: [1] A. Ciamei, S. Finelli, M. Inguscio, A. Trenkwalder, and M. Zaccanti, "All-optical Production of Ultracold 6Li-53Cr Fermi Mixtures", in preparation
[2] A. Ciamei, S. Finelli, M. Inguscio, A. Trenkwalder, A. Simoni, D. Petrov, and M. Zaccanti, "Feshbach Resonances in Ultracold 6Li-53Cr Fermi Mixtures", in preparation
Presenters
-
Alessio Ciamei
- Consiglio Nazionale delle Ricerche (CNR-INO)