Taming, slowing and trapping atoms with light
Cold is quantum, Quantum is cool!
Multicolored lasers for a variety of different atoms
Keeping our eyes on the quantum
High technology for great science
Join our ultracool group!

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!

LAST NEWS

We report on the experimental observation of a strongly interacting gas of ultracold two-electron fermions with an orbital degree of freedom and magnetically tunable interactions. This realization has been enabled by the demonstration of a novel kind of Feshbach resonance occurring in the scattering of two 173Yb atoms in different nuclear and electronic states. The strongly interacting regime at resonance is evidenced by the observation of anisotropic hydrodynamic expansion of the two-orbital Fermi gas. These results pave the way towards the realization of new quantum states of matter with strongly correlated fermions with an orbital degree of freedom.

G. Pagano et al.,
Strongly Interacting Gas of Two-Electron Fermions at an Orbital Feshbach Resonance
Phys. Rev. Lett. 115, 265301 (2015)

See also the Physics Viewpoint by S. Cornish:

S. Cornish
Controlling Collisions in a Two-Electron Atomic Gas
Physics 8, 125 (2015)

In ultracold atoms settings, inelastic light scattering is a preeminent technique to reveal static and dynamic properties at nonzero momentum. In this work, we investigate an array of one-dimensional trapped Bose gases, by measuring both the energy and the momentum imparted to the system via light scattering experiments. The measurements are performed in the weak perturbation regime, where these two quantities — the energy and momentum transferred — are expected to be related to the dynamic structure factor of the system. We discuss this relation, with special attention to the role of in-trap dynamics on the transferred momentum.

N. Fabbri et al.,
Energy and momentum transfer in one-dimensional trapped gases by stimulated light scattering
New J. Phys. 17, 063012 (2015)

Entanglement is a fundamental resource for quantum information processing, occurring naturally in many-body systems at low temperatures. The presence of entanglement and, in particular, its scaling with the size of system partitions underlies the complexity of quantum many-body states. The quantitative estimation of entanglement in many-body systems represents a major challenge, as it requires either full-state tomography, scaling exponentially in the system size, or the assumption of unverified system characteristics such as its Hamiltonian or temperature. Here we adopt recently developed approaches for the determination of rigorous lower entanglement bounds from readily accessible measurements and apply them in an experiment of ultracold interacting bosons in optical lattices of 105 sites. We then study the behaviour of spatial entanglement between the sites when crossing the superfluid-Mott insulator transition and when varying temperature. This constitutes the first rigorous experimental large-scale entanglement quantification in a scalable quantum simulator.

M. Cramer et al.,
Spatial entanglement of bosons in optical lattices
Nat. Commun. 4, 2161 (2013)

We report the Bragg spectroscopy of interacting one-dimensional Bose gases loaded in an optical lattice across the superfluid to the Mott-insulator phase transition. Elementary excitations are created with a nonzero momentum and the response of the correlated 1D gases is in the linear regime. The complexity of the strongly correlated quantum phases is directly displayed in the spectra which exhibit novel features. This work paves the way for a precise characterization of the state of correlated gases in optical lattices.

D. Clément et al.,
Spatial entanglement of bosons in optical lattices
Phys. Rev. Lett. 102, 105301 (2009)

See also the Physics Viewpoint by D. Jaksch:

D. Jaksch
A stimulated atomic response
Physics 2, 29 (2009)

Last Tweets

Seminars & Events

13.06.2017
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.
20 & 21.04.2017
QUIC Project Meeting
See detailed program
Querzoli room, LENS.
10.04.2017
Seminar by Prof. Nick Proukakis:
Non-Equilibrium Dynamics in Quantum Gases,
h. 11.00 Querzoli room, LENS.
23.02.2017
Seminar by Prof. David Clément:
Momentum-resolved investigation of the condensate depletion in interacting Bose gases,
h. 15.00 Querzoli room, LENS.
22.02.2017
Seminar by Dr. Carmine Ortix:
Symmetry-protected topological insulators in one-dimension,
h. 12.00 Querzoli room, LENS.
08.02.2017
Trento-Florence Joint Meeting on Cold Matter
Polo Scientifico di Povo, Trento.
24.01.2017
Seminar by Dr. Franck Pereira Dos Santos:
Cold Atom Interferometry Gravity Sensors,
h.15.15 Querzoli room, LENS.
20.01.2017
Seminar by Andrea Morales:
Supersolid formation in a quantum gas breaking a continuous translational symmetry,
h.15.15 Querzoli room, LENS.
20.01.2017
Seminar by Prof. Jean-Philippe Brantut:
Mesoscopic transport experiments with cold atoms,
h. 11.00 Querzoli room, LENS.
19.12.2016
Seminar by Dr. Guido Pagano:
Observation of a Discrete Time Crystal in a Trapped-Ion Quantum Simulator,
h. 16.30 Querzoli room, LENS.
10.10.2016
Seminar by Dr. Francesco Piazza:
Spontaneous Crystallisation of Light and Ultracold Atoms,
h. 15.00 Querzoli room, LENS.
16.09.2016
Fermi Colloquim by Prof. Jun Ye:
Optical atomic clock and many-body quantum physics,
h. 11.30 Querzoli room, LENS.