We report the realization of a Bose-Einstein condensate of M. Landini et al., Phys. Rev. A 86, 033421 (2012) |

Welcome to the website of the Ultracold Quantum Gases group at the European Laboratory for Nonlinear Spectroscopy (LENS) and Department of Physics and Astronomy of the University of Florence (Italy). In our labs we use lasers and magnetic fields to produce the lowest temperatures of the Universe, just a few billionths of a degree above absolute zero...

At these temperatures, atoms stop moving and we can control them for a variety of different fundamental studies and applications. We can force atoms to arrange according to a periodic structure and simulate the behavior of crystalline solids and new materials. We can use the atoms as ultra-high accurate sensors to probe forces with the power of quantum mechanics. We can study how quantum particles combine together under the action of strong interactions and how superfluidity develops. We can use these ultracold atoms to process information and develop new quantum technologies.

Dress warmly and... follow us for this ultracold journey!

We report the realization of a Bose-Einstein condensate of M. Landini et al., Phys. Rev. A 86, 033421 (2012) |

Driving the complex dynamics of physical systems to perform a specific task is extremely useful but challenging in several fields of science, and especially for fragile quantum mechanical systems. Even harder, and often unfeasible, is to invert the time arrow of the dynamics, undoing some physical process. We theoretically and experimentally drive forth and back through several paths in the five-level Hilbert space of a Rubidium atom in the ground state. We achieve such an objective applying optimal control strategies to a Bose-Einstein condensate on an Atom chip via a frequency modulated RF field. We further prove that backward dynamical evolution does not correspond to simply inverting the time arrow of the driving field neglecting the only-system part of the dynamics. Apart from the relevance for the foundations of quantum mechanics, these results are important steps forward in the manipulation of quantum dynamics that is crucial for several physical implementations and very promisingly powerful quantum technologies. C. Lovecchio et al., |

Chiral edge states are a hallmark of quantum Hall physics. In electronic systems, they appear as a macroscopic consequence of the cyclotron orbits induced by a magnetic field, which are naturally truncated at the physical boundary of the sample. Here we report on the experimental realization of chiral edge states in a ribbon geometry with an ultracold gas of neutral fermions subjected to an artificial gauge field. By imaging individual sites along a synthetic dimension, we detect the existence of the edge states, investigate the onset of chirality as a function of the bulk-edge coupling, and observe the edge-cyclotron orbits induced during a quench dynamics. The realization of fermionic chiral edge states is a fundamental achievement, which opens the door towards experiments including edge state interferometry and the study of non-Abelian anyons in atomic systems. M. Mancini et al., See also the Science Perspective by A. Celi and L. Tarruell: A. Celi and L. Tarruell |

It is generally impossible to probe a quantum system without disturbing it. However, it is possible to exploit the back-action of quantum measurements and strong couplings to tailor and protect the coherent evolution of a quantum system. This is a profound and counterintuitive phenomenon known as quantum Zeno dynamics (QZD). Here we demonstrate QZD with a rubidium Bose-Einstein condensate in a five-level Hilbert space. We harness measurements and strong couplings to dynamically disconnect different groups of quantum states and constrain the atoms to coherently evolve inside a two-level subregion. In parallel to the foundational importance due to the realization of a dynamical superselection rule and the theory of quantum measurements, this is an important step forward in protecting and controlling quantum dynamics and, broadly speaking, quantum information processing. F. Schӓfer et al., S. Gherardini et al., |

The LENS QuantumGases group is glad to welcome in Florence Prof. Randall Hulet from Rice University. Prof. Hulet will be our guest for one month until mid July.

Seminar by Prof. Nick Proukakis:

*Non-Equilibrium Dynamics in Quantum Gases*,

h. 11.00 Querzoli room, LENS.

h. 11.00 Querzoli room, LENS.

Seminar by Prof. David Clément:

*Momentum-resolved investigation of the condensate depletion in interacting Bose gases*,

h. 15.00 Querzoli room, LENS.

h. 15.00 Querzoli room, LENS.

Seminar by Dr. Carmine Ortix:

*Symmetry-protected topological insulators in one-dimension*,

h. 12.00 Querzoli room, LENS.

h. 12.00 Querzoli room, LENS.

Trento-Florence Joint Meeting on Cold Matter

Polo Scientifico di Povo, Trento.

Polo Scientifico di Povo, Trento.

Seminar by Dr. Franck Pereira Dos Santos:

*Cold Atom Interferometry Gravity Sensors*,

h.15.15 Querzoli room, LENS.

h.15.15 Querzoli room, LENS.

Seminar by Andrea Morales:

*Supersolid formation in a quantum gas breaking a continuous translational symmetry*,

h.15.15 Querzoli room, LENS.

h.15.15 Querzoli room, LENS.

Seminar by Prof. Jean-Philippe Brantut:

*Mesoscopic transport experiments with cold atoms*,

h. 11.00 Querzoli room, LENS.

h. 11.00 Querzoli room, LENS.

Seminar by Dr. Guido Pagano:

*Observation of a Discrete Time Crystal in a Trapped-Ion Quantum Simulator*,

h. 16.30 Querzoli room, LENS.

h. 16.30 Querzoli room, LENS.

Seminar by Dr. Francesco Piazza:

*Spontaneous Crystallisation of Light and Ultracold Atoms*,

h. 15.00 Querzoli room, LENS.

h. 15.00 Querzoli room, LENS.

Fermi Colloquim by Prof. Jun Ye:

*Optical atomic clock and many-body quantum physics*,

h. 11.30 Querzoli room, LENS.

h. 11.30 Querzoli room, LENS.