Publications (42)
Collisional properties of ultracold K-Rb mixtures
G. Ferrari, M. Inguscio, W. Jastrzebski +3
We determine the inter-species s-wave triplet scattering length a3 for all K-Rb isotopic mixtures by measuring the cross-section for collisions between 41K and 87Rb in different te…
Observation of Quantum Phase Transitions with Parity-Symmetry Breaking and Hysteresis
A. Trenkwalder, G. Spagnolli, G. Semeghini +8
Symmetry-breaking quantum phase transitions play a key role in several condensed matter, cosmology and nuclear physics theoretical models. Its observation in real systems is often…
Sub-Doppler laser cooling of potassium atoms
M. Landini, S. Roy, L. Carcagni' +4
We investigate sub-Doppler laser cooling of bosonic potassium isotopes, whose small hyperfine splitting has so far prevented cooling below the Doppler temperature. We find instead…
39-K Bose-Einstein condensate with tunable interactions
G. Roati, M. Zaccanti, C. D'Errico +5
We produce a Bose-Einstein condensate of 39-K atoms. Condensation of this species with naturally small and negative scattering length is achieved by a combination of sympathetic co…
Control of the interaction in a Fermi-Bose mixture
M. Zaccanti, C. D'Errico, F. Ferlaino +3
We control the interspecies interaction in a two-species atomic quantum mixture by tuning the magnetic field at a Feshbach resonance. The mixture is composed by fermionic 40K and b…
Sub-Doppler Laser Cooling of Fermionic K-40 Atoms
G. Modugno, C. Benko, P. Hannaford +2
We report laser cooling of fermionic K-40 atoms, with temperatures down to (15 +/- 5) microK, for an enriched sample trapped in a MOT and additionaly cooled in optical molasses. Th…
Dimensional crossover in the superfluid-supersolid quantum phase transition
G. Biagioni, N. Antolini, A. Alaña +5
We assess experimentally and theoretically the character of the superfluid-supersolid quantum phase transition recently discovered in trapped dipolar quantum gases. We find that on…
Dipolar oscillations in a quantum degenerate Fermi-Bose atomic mixture
F. Ferlaino, R. J. Brecha, P. Hannaford +4
We study the dynamics of coupled dipolar oscillations in a Fermi-Bose mixture of K and Rb atoms. This low-energy collective mode is strongly affected by the interspec…
Crossing Over from Attractive to Repulsive Interactions in a Tunneling Bosonic Josephson Junction
G. Spagnolli, G. Semeghini, L. Masi +9
We explore the interplay between tunneling and interatomic interactions in the dynamics of a bosonic Josephson junction. We tune the scattering length of an atomic K Bose-Ei…
Quantum diffusion with disorder, noise and interaction
C. D'Errico, M. Moratti, E. Lucioni +6
Disorder, noise and interaction play a crucial role in the transport properties of real systems, but they are typically hard to control and study both theoretically and experimenta…
Feshbach resonances in ultracold K(39)
C. D'Errico, M. Zaccanti, M. Fattori +4
We discover several magnetic Feshbach resonances in collisions of ultracold K(39) atoms, by studying atom losses and molecule formation. Accurate determination of the magnetic-fiel…
Fermi-Bose quantum degenerate ^40 K - ^87 Rb mixture with attractive interaction
G. Roati, F. Riboli, G. Modugno +1
We report on the achievement of simultaneous quantum degeneracy in a mixed gas of fermionic ^40 K and bosonic ^87 Rb. Potassium is cooled to 0.3 times the Fermi temperature by mean…
Delocalization of a disordered bosonic system by repulsive interactions
B. Deissler, M. Zaccanti, G. Roati +5
Clarifying the interplay of interactions and disorder is fundamental to the understanding of many quantum systems, including superfluid helium in porous media, granular and thin-fi…
Atom Interferometry in a Vertical Optical Lattice
G. Modugno, E. de Mirandes, F. Ferlaino +3
We have studied the interference of degenerate quantum gases in a vertical optical lattice. The coherence of the atoms leads to an interference pattern when the atoms are released…
A two atomic species superfluid
G. Modugno, M. Modugno, F. Riboli +2
We produce a quantum degenerate mixture composed by two Bose-Einstein condensates of different atomic species, 41 K and 87 Rb. We study the dynamics of the superfluid system in an…
Mott Transition for Strongly-Interacting 1D Bosons in a Shallow Periodic Potential
G. Boéris, L. Gori, M. D. Hoogerland +9
We investigate the superfluid-insulator transition of one-dimensional interacting Bosons in both deep and shallow periodic potentials. We compare a theoretical analysis based on Mo…
Observation of an Efimov spectrum in an atomic system
M. Zaccanti, B. Deissler, C. D'Errico +6
In 1970 V. Efimov predicted a puzzling quantum-mechanical effect that is still of great interest today. He found that three particles subjected to a resonant pairwise interaction c…
Insulating Behavior of a Trapped Ideal Fermi Gas
L. Pezze', L. Pitaevskii, A. Smerzi +7
We investigate theoretically and experimentally the center-of-mass motion of an ideal Fermi gas in a combined periodic and harmonic potential. We find a crossover from a conducting…
Collisionally Induced Transport in Periodic Potentials
H. Ott, E. de Mirandes, F. Ferlaino +3
We study the transport of ultra cold atoms in a tight optical lattice. For identical fermions the system is insulating under an external force while for bosonic atoms it is conduct…
Supersolid symmetry breaking from compressional oscillations in a dipolar quantum gas
L. Tanzi, S. M. Roccuzzo, E. Lucioni +6
The existence of a paradoxical supersolid phase of matter, possessing the apparently incompatible properties of crystalline order and superfluidity, was predicted 50 years ago. Sol…
A new setup for experiments with ultracold Dysprosium atoms
E. Lucioni, G. Masella, A. Fregosi +7
In the domain of quantum degenerate atomic gases, much interest has been raised recently by the use of Lanthanide atoms with large magnetic moments, in particular Dysprosium and Er…
Mean-field analysis of the stability of a K-Rb Fermi-Bose mixture
M. Modugno, F. Ferlaino, F. Riboli +3
We compare the experimental stability diagram of a Fermi-Bose mixture of K-40 and Rb-87 atoms with attractive interaction to the predictions of a mean-field theoretical model. We d…
Expansion of a Fermi gas interacting with a Bose-Einstein condensate
F. Ferlaino, E. de Mirandes, G. Roati +2
We study the expansion of an atomic Fermi gas interacting attractively with a Bose-Einstein condensate. We find that the interspecies interaction affects dramatically both the expa…
Spatial Bloch oscillations of a quantum gas in a "beat-note" superlattice
L. Masi, T. Petrucciani, G. Ferioli +4
We report the experimental realization of a new kind of optical lattice for ultra-cold atoms where arbitrarily large separation between the sites can be achieved without renouncing…
Radio Frequency Selective Addressing of Localized Particles in a Periodic Potential
H. Ott, E. de Mirandes, F. Ferlaino +4
We study the localization and addressability of ultra cold atoms in a combined parabolic and periodic potential. Such a potential supports the existence of localized stationary sta…
Anderson localization of a non-interacting Bose-Einstein condensate
G. Roati, C. D'Errico, L. Fallani +6
One of the most intriguing phenomena in physics is the localization of waves in disordered media. This phenomenon was originally predicted by Anderson, fifty years ago, in the cont…
Magnetic control of the interaction in ultracold K-Rb mixtures
A. Simoni, F. Ferlaino, G. Roati +2
We predict the presence of several magnetic Feshbach resonances in selected Zeeman sublevels of the isotopic pairs K(40)-Rb(87) and K(41)-Rb(87) at magnetic fields up to 1000 G. Po…
Cooling atoms in an optical trap by selective parametric excitation
N. Poli, R. J. Brecha, G. Roati +1
We demonstrate the possibility of energy-selective removal of cold atoms from a tight optical trap by means of parametric excitation of the trap vibrational modes. Taking advantage…
Magnetic dipolar interaction in an atomic Bose Einstein condensate interferometer
M. Fattori, G. Roati, B. Deissler +6
We study the role played by the magnetic dipole interaction in an atomic interferometer based on an alkali Bose-Einstein condensate with tunable scattering length. We tune the s-wa…
Anharmonic parametric excitation in optical lattices
R. Jáuregui, N. Poli, G. Roati +1
We study both experimentally and theoretically the losses induced by parametric excitation in far-off-resonance optical lattices. The atoms confined in a 1D sinusoidal lattice pres…
Accurate near-threshold model for ultracold KRb dimers from interisotope Feshbach spectroscopy
A. Simoni, M. Zaccanti, C. D'Errico +4
We investigate magnetic Feshbach resonances in two different ultracold K-Rb mixtures. Information on the K(39)-Rb(87) isotopic pair is combined with novel and pre-existing observat…
An Optical Trap for Collisional Studies on Cold Fermionic Potassium
G. Roati, W. Jastrzebski, A. Simoni +2
We report on trapping of fermionic 40K atoms in a red-detuned standing-wave optical trap, loaded from a magneto-optical trap. Typically, 10^6 atoms are loaded at a density of 10^12…
Dysprosium dipolar Bose-Einstein condensate with broad Feshbach resonances
E. Lucioni, L. Tanzi, A. Fregosi +6
We produce Bose-Einstein condensates of Dy atoms employing an innovative technique based on a resonator-enhanced optical trap that allows efficient loading from the magneto…
Atom interferometry with trapped Fermi gases
G. Roati, E. de Mirandes, F. Ferlaino +3
We realize an interferometer with an atomic Fermi gas trapped in an optical lattice under the influence of gravity. The single-particle interference between the eigenstates of the…
Observation of subdiffusion of a disordered interacting system
E. Lucioni, B. Deissler, L. Tanzi +7
We study the transport dynamics of matter-waves in the presence of disorder and nonlinearity. An atomic Bose-Einstein condensate that is localized in a quasiperiodic lattice in the…
Comparative investigation of 39K and 40K trap loss rates: alternative loss channel at low light intensities
G. Modugno, G. Roati, M. Inguscio +4
We report a comparative investigation of trap loss rates in a magneto-optical trap for two potassium isotopes, 39K and 40K, as a function of trap light intensity. The isotopes pres…
Evidence of superfluidity in a dipolar supersolid from non-classical rotational inertia
L. Tanzi, J. G. Maloberti, G. Biagioni +3
A key manifestation of superfluidity in liquids and gases is a reduction of the moment of inertia under slow rotations. Non-classical rotational effects have been searched for a lo…
Enhancement of the scissors mode of an expanding Bose-Einstein condensate
M. Modugno, G. Modugno, G. Roati +2
We study the time-evolution of the scissors mode of a Bose-Einstein condensate during the ballistic expansion after release from the magnetic trap. We show that despite the nontriv…
Production of a Fermi gas of atoms in an optical lattice
G. Modugno, F. Ferlaino, R. Heidemann +2
We prepare a degenerate Fermi gas of potassium atoms by sympathetic cooling with rubidium atoms in a one-dimensional optical lattice. In a tight lattice we observe a change of the…
High-resolution spectroscopy of 162Dy Rydberg levels
G. Ferioli, P. Lombardi, P. Sekhar +9
Highly excited Rydberg states of lanthanides are a promising, yet largely unexplored, playground for quantum studies. Here, we report on the first high-resolution spectroscopy of 1…
Self-bound quantum droplets in atomic mixtures
G. Semeghini, G. Ferioli, L. Masi +7
Self-bound quantum droplets are a newly discovered phase in the context of ultracold atoms. In this work we report their experimental realization following the original proposal by…
Correlation function of weakly interacting bosons in a disordered lattice
B. Deissler, E. Lucioni, M. Modugno +5
One of the most important issues in disordered systems is the interplay of the disorder and repulsive interactions. Several recent experimental advances on this topic have been mad…