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Zhou TW, Cappellini G, Tusi D, Franchi L, Parravicini J, Repellin C, Greschner S, Inguscio M, Giamarchi T, Filippone M, Catani J, Fallani L. Observation of universal Hall response in strongly interacting Fermions. Science 2023; 381:427-430. [PMID: 37498998 DOI: 10.1126/science.add1969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 06/14/2023] [Indexed: 07/29/2023]
Abstract
The Hall effect, which originates from the motion of charged particles in magnetic fields, has deep consequences for the description of materials, extending far beyond condensed matter. Understanding such an effect in interacting systems represents a fundamental challenge, even for small magnetic fields. In this work, we used an atomic quantum simulator in which we tracked the motion of ultracold fermions in two-leg ribbons threaded by artificial magnetic fields. Through controllable quench dynamics, we measured the Hall response for a range of synthetic tunneling and atomic interaction strengths. We unveil a universal interaction-independent behavior above an interaction threshold, in agreement with theoretical analyses. The ability to reach hard-to-compute regimes demonstrates the power of quantum simulation to describe strongly correlated topological states of matter.
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Affiliation(s)
- T-W Zhou
- Department of Physics and Astronomy, University of Florence, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), Sezione di Sesto Fiorentino, 50019 Sesto Fiorentino, Italy
| | - G Cappellini
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), Sezione di Sesto Fiorentino, 50019 Sesto Fiorentino, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
| | - D Tusi
- European Laboratory for Non-Linear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
| | - L Franchi
- Department of Physics and Astronomy, University of Florence, 50019 Sesto Fiorentino, Italy
| | - J Parravicini
- Department of Physics and Astronomy, University of Florence, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), Sezione di Sesto Fiorentino, 50019 Sesto Fiorentino, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
| | - C Repellin
- Université Grenoble Alpes, CNRS, LPMMC, 38000 Grenoble, France
| | - S Greschner
- Department of Quantum Matter Physics, University of Geneva, 1211 Geneva, Switzerland
| | - M Inguscio
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), Sezione di Sesto Fiorentino, 50019 Sesto Fiorentino, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
- Department of Engineering, Campus Bio-Medico University of Rome, 00128 Rome, Italy
| | - T Giamarchi
- Department of Quantum Matter Physics, University of Geneva, 1211 Geneva, Switzerland
| | - M Filippone
- Université Grenoble Alpes, CEA, IRIG-MEM-L_SIM, 38000 Grenoble, France
| | - J Catani
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), Sezione di Sesto Fiorentino, 50019 Sesto Fiorentino, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
| | - L Fallani
- Department of Physics and Astronomy, University of Florence, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), Sezione di Sesto Fiorentino, 50019 Sesto Fiorentino, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
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2
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Ciamei A, Finelli S, Trenkwalder A, Inguscio M, Simoni A, Zaccanti M. Exploring Ultracold Collisions in ^{6}Li-^{53}Cr Fermi Mixtures: Feshbach Resonances and Scattering Properties of a Novel Alkali-Transition Metal System. Phys Rev Lett 2022; 129:093402. [PMID: 36083677 DOI: 10.1103/physrevlett.129.093402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 05/12/2022] [Accepted: 07/21/2022] [Indexed: 06/15/2023]
Abstract
We investigate ultracold collisions in a novel mixture of ^{6}Li and ^{53}Cr fermionic atoms, discovering more than 50 interspecies Feshbach resonances via loss spectroscopy. Building a full coupled-channel model, we unambiguously characterize the ^{6}Li-^{53}Cr scattering properties and yield predictions for other isotopic pairs. In particular, we identify various Feshbach resonances that enable the controlled tuning of elastic s- and p-wave ^{6}Li-^{53}Cr interactions. Our studies thus make lithium-chromium mixtures emerge as optimally suited platforms for the experimental search of elusive few- and many-body regimes of highly correlated fermionic matter, and for the realization of a new class of ultracold polar molecules possessing both electric and magnetic dipole moments.
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Affiliation(s)
- A Ciamei
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - S Finelli
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - A Trenkwalder
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - M Inguscio
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, 50019 Sesto Fiorentino, Italy
- Department of Engineering, Campus Bio-Medico University of Rome, 00128 Rome, Italy
| | - A Simoni
- Univ Rennes, CNRS, IPR (Institut de Physique de Rennes)-UMR 6251, F-35000 Rennes, France
| | - M Zaccanti
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
- European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, 50019 Sesto Fiorentino, Italy
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3
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Kwon WJ, Del Pace G, Xhani K, Galantucci L, Muzi Falconi A, Inguscio M, Scazza F, Roati G. Sound emission and annihilations in a programmable quantum vortex collider. Nature 2021; 600:64-69. [PMID: 34853459 DOI: 10.1038/s41586-021-04047-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 09/22/2021] [Indexed: 11/09/2022]
Abstract
In quantum fluids, the quantization of circulation forbids the diffusion of a vortex swirling flow seen in classical viscous fluids. Yet, accelerating quantum vortices may lose their energy into acoustic radiations1,2, similar to the way electric charges decelerate on emitting photons. The dissipation of vortex energy underlies central problems in quantum hydrodynamics3, such as the decay of quantum turbulence, highly relevant to systems as varied as neutron stars, superfluid helium and atomic condensates4,5. A deep understanding of the elementary mechanisms behind irreversible vortex dynamics has been a goal for decades3,6, but it is complicated by the shortage of conclusive experimental signatures7. Here we address this challenge by realizing a programmable vortex collider in a planar, homogeneous atomic Fermi superfluid with tunable inter-particle interactions. We create on-demand vortex configurations and monitor their evolution, taking advantage of the accessible time and length scales of ultracold Fermi gases8,9. Engineering collisions within and between vortex-antivortex pairs allows us to decouple relaxation of the vortex energy due to sound emission and that due to interactions with normal fluid (that is, mutual friction). We directly visualize how the annihilation of vortex dipoles radiates a sound pulse. Further, our few-vortex experiments extending across different superfluid regimes reveal non-universal dissipative dynamics, suggesting that fermionic quasiparticles localized inside the vortex core contribute significantly to dissipation, thereby opening the route to exploring new pathways for quantum turbulence decay, vortex by vortex.
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Affiliation(s)
- W J Kwon
- European Laboratory for Nonlinear Spectroscopy (LENS), Sesto Fiorentino, Italy. .,Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), Sesto Fiorentino, Italy.
| | - G Del Pace
- European Laboratory for Nonlinear Spectroscopy (LENS), Sesto Fiorentino, Italy.,Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), Sesto Fiorentino, Italy
| | - K Xhani
- European Laboratory for Nonlinear Spectroscopy (LENS), Sesto Fiorentino, Italy.,Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), Sesto Fiorentino, Italy
| | - L Galantucci
- Joint Quantum Centre (JQC) Durham-Newcastle, School of Mathematics, Statistics and Physics, Newcastle University, Newcastle upon Tyne, UK
| | - A Muzi Falconi
- European Laboratory for Nonlinear Spectroscopy (LENS), Sesto Fiorentino, Italy.,Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), Sesto Fiorentino, Italy
| | - M Inguscio
- European Laboratory for Nonlinear Spectroscopy (LENS), Sesto Fiorentino, Italy.,Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), Sesto Fiorentino, Italy.,Department of Engineering, Campus Bio-Medico University of Rome, Rome, Italy
| | - F Scazza
- European Laboratory for Nonlinear Spectroscopy (LENS), Sesto Fiorentino, Italy.,Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), Sesto Fiorentino, Italy.,Department of Physics, University of Trieste, Trieste, Italy
| | - G Roati
- European Laboratory for Nonlinear Spectroscopy (LENS), Sesto Fiorentino, Italy.,Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), Sesto Fiorentino, Italy
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4
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Masi L, Petrucciani T, Ferioli G, Semeghini G, Modugno G, Inguscio M, Fattori M. Spatial Bloch Oscillations of a Quantum Gas in a "Beat-Note" Superlattice. Phys Rev Lett 2021; 127:020601. [PMID: 34296908 DOI: 10.1103/physrevlett.127.020601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 03/17/2021] [Accepted: 06/14/2021] [Indexed: 06/13/2023]
Abstract
We report the experimental realization of a new kind of optical lattice for ultracold atoms where arbitrarily large separation between the sites can be achieved without renouncing to the stability of ordinary lattices. Two collinear lasers, with slightly different commensurate wavelengths and retroreflected on a mirror, generate a superlattice potential with a periodic "beat-note" profile where the regions with large amplitude modulation provide the effective potential minima for the atoms. To prove the analogy with a standard large spacing optical lattice we study Bloch oscillations of a Bose Einstein condensate with negligible interactions in the presence of a small force. The observed dynamics between sites separated by ten microns for times exceeding one second proves the high stability of the potential. This novel lattice is the ideal candidate for the coherent manipulation of atomic samples at large spatial separations and might find direct application in atom-based technologies like trapped-atom interferometers and quantum simulators.
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Affiliation(s)
- L Masi
- CNR Istituto Nazionale Ottica, 50019 Sesto Fiorentino, Italy
| | - T Petrucciani
- European Laboratory for Nonlinear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
| | - G Ferioli
- CNR Istituto Nazionale Ottica, 50019 Sesto Fiorentino, Italy
| | - G Semeghini
- CNR Istituto Nazionale Ottica, 50019 Sesto Fiorentino, Italy
| | - G Modugno
- CNR Istituto Nazionale Ottica, 50019 Sesto Fiorentino, Italy
- European Laboratory for Nonlinear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
- Department of Physics and Astronomy, University of Florence, 50019 Sesto Fiorentino, Italy
| | - M Inguscio
- CNR Istituto Nazionale Ottica, 50019 Sesto Fiorentino, Italy
- European Laboratory for Nonlinear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
- Department of Engineering, Campus Bio-Medico University of Rome, 00128 Rome, Italy
| | - M Fattori
- CNR Istituto Nazionale Ottica, 50019 Sesto Fiorentino, Italy
- European Laboratory for Nonlinear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
- Department of Physics and Astronomy, University of Florence, 50019 Sesto Fiorentino, Italy
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5
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Kwon WJ, Del Pace G, Panza R, Inguscio M, Zwerger W, Zaccanti M, Scazza F, Roati G. Strongly correlated superfluid order parameters from dc Josephson supercurrents. Science 2020; 369:84-88. [DOI: 10.1126/science.aaz2463] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 04/27/2020] [Indexed: 11/02/2022]
Affiliation(s)
- W. J. Kwon
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
- European Laboratory for Nonlinear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
| | - G. Del Pace
- European Laboratory for Nonlinear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
- Department of Physics and Astronomy, University of Florence, 50019 Sesto Fiorentino, Italy
| | - R. Panza
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
- European Laboratory for Nonlinear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
| | - M. Inguscio
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
- European Laboratory for Nonlinear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
- Department of Engineering, Campus Bio-Medico University of Rome, 00128 Rome, Italy
| | - W. Zwerger
- Physics Department, Technische Universität München, 85747 Garching, Germany
| | - M. Zaccanti
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
- European Laboratory for Nonlinear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
| | - F. Scazza
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
- European Laboratory for Nonlinear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
| | - G. Roati
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
- European Laboratory for Nonlinear Spectroscopy (LENS), 50019 Sesto Fiorentino, Italy
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6
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Xhani K, Neri E, Galantucci L, Scazza F, Burchianti A, Lee KL, Barenghi CF, Trombettoni A, Inguscio M, Zaccanti M, Roati G, Proukakis NP. Critical Transport and Vortex Dynamics in a Thin Atomic Josephson Junction. Phys Rev Lett 2020; 124:045301. [PMID: 32058733 DOI: 10.1103/physrevlett.124.045301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Indexed: 06/10/2023]
Abstract
We study the onset of dissipation in an atomic Josephson junction between Fermi superfluids in the molecular Bose-Einstein condensation limit of strong attraction. Our simulations identify the critical population imbalance and the maximum Josephson current delimiting dissipationless and dissipative transport, in quantitative agreement with recent experiments. We unambiguously link dissipation to vortex ring nucleation and dynamics, demonstrating that quantum phase slips are responsible for the observed resistive current. Our work directly connects microscopic features with macroscopic dissipative transport, providing a comprehensive description of vortex ring dynamics in three-dimensional inhomogeneous constricted superfluids at zero and finite temperatures.
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Affiliation(s)
- K Xhani
- Joint Quantum Centre (JQC) Durham-Newcastle, School of Mathematics, Statistics and Physics, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
- European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - E Neri
- Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - L Galantucci
- Joint Quantum Centre (JQC) Durham-Newcastle, School of Mathematics, Statistics and Physics, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
| | - F Scazza
- European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
| | - A Burchianti
- European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
| | - K-L Lee
- Joint Quantum Centre (JQC) Durham-Newcastle, School of Mathematics, Statistics and Physics, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
| | - C F Barenghi
- Joint Quantum Centre (JQC) Durham-Newcastle, School of Mathematics, Statistics and Physics, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
| | - A Trombettoni
- CNR-IOM DEMOCRITOS Simulation Center and SISSA, Via Bonomea 265, I-34136 Trieste, Italy
| | - M Inguscio
- European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
- Department of Engineering, Campus Bio-Medico University of Rome, 00128 Rome, Italy
| | - M Zaccanti
- European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, 50019 Sesto Fiorentino, Italy
- Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
| | - G Roati
- European Laboratory for Non-Linear Spectroscopy (LENS), Università di Firenze, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (CNR-INO), 50019 Sesto Fiorentino, Italy
| | - N P Proukakis
- Joint Quantum Centre (JQC) Durham-Newcastle, School of Mathematics, Statistics and Physics, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom
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Simonelli C, Neri E, Ciamei A, Goti I, Inguscio M, Trenkwalder A, Zaccanti M. Realization of a high power optical trapping setup free from thermal lensing effects. Opt Express 2019; 27:27215-27228. [PMID: 31674587 DOI: 10.1364/oe.27.027215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 07/01/2019] [Indexed: 06/10/2023]
Abstract
Transmission of high power laser beams through partially absorbing materials modifies the light propagation via a thermally-induced effect known as thermal lensing. This may cause changes in the beam waist position and degrade the beam quality. Here we characterize the effect of thermal lensing associated with the different elements typically employed in an optical trapping setup for cold atoms experiments. We find that the only relevant thermal lens is represented by the TeO2 crystal of the acousto-optic modulator exploited to adjust the laser power on the atomic sample. We then devise a simple and totally passive scheme that enables to realize an inexpensive optical trapping apparatus essentially free from thermal lensing effects.
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8
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Amico A, Scazza F, Valtolina G, Tavares PES, Ketterle W, Inguscio M, Roati G, Zaccanti M. Time-Resolved Observation of Competing Attractive and Repulsive Short-Range Correlations in Strongly Interacting Fermi Gases. Phys Rev Lett 2018; 121:253602. [PMID: 30608797 DOI: 10.1103/physrevlett.121.253602] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Indexed: 06/09/2023]
Abstract
We exploit a time-resolved pump-probe spectroscopic technique to study the out-of-equilibrium dynamics of an ultracold two-component Fermi gas, selectively quenched to strong repulsion along the upper branch of a broad Feshbach resonance. For critical interactions, we find the rapid growth of short-range anticorrelations between repulsive fermions to initially overcome concurrent pairing processes. At longer evolution times, these two competing mechanisms appear to macroscopically coexist in a short-range correlated state of fermions and pairs, unforeseen thus far. Our work provides fundamental insights into the fate of a repulsive Fermi gas, and offers new perspectives towards the exploration of complex dynamical regimes of fermionic matter.
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Affiliation(s)
- A Amico
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
| | - F Scazza
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
| | - G Valtolina
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
| | - P E S Tavares
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
| | - W Ketterle
- Department of Physics, MIT-Harvard Center for Ultracold Atoms, and Research Laboratory of Electronics, MIT, Cambridge, Massachusetts 02139, USA
| | - M Inguscio
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
| | - G Roati
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
| | - M Zaccanti
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
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9
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Semeghini G, Ferioli G, Masi L, Mazzinghi C, Wolswijk L, Minardi F, Modugno M, Modugno G, Inguscio M, Fattori M. Self-Bound Quantum Droplets of Atomic Mixtures in Free Space. Phys Rev Lett 2018; 120:235301. [PMID: 29932719 DOI: 10.1103/physrevlett.120.235301] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Indexed: 06/08/2023]
Abstract
Self-bound quantum droplets are a newly discovered phase in the context of ultracold atoms. In this Letter, we report their experimental realization following the original proposal by Petrov [Phys. Rev. Lett. 115, 155302 (2015)PRLTAO0031-900710.1103/PhysRevLett.115.155302], using an attractive bosonic mixture. In this system, spherical droplets form due to the balance of competing attractive and repulsive forces, provided by the mean-field energy close to the collapse threshold and the first-order correction due to quantum fluctuations. Thanks to an optical levitating potential with negligible residual confinement, we observe self-bound droplets in free space, and we characterize the conditions for their formation as well as their size and composition. This work sets the stage for future studies on quantum droplets, from the measurement of their peculiar excitation spectrum to the exploration of their superfluid nature.
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Affiliation(s)
- G Semeghini
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- CNR Istituto Nazionale Ottica, 50019 Sesto Fiorentino, Italy
| | - G Ferioli
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- CNR Istituto Nazionale Ottica, 50019 Sesto Fiorentino, Italy
| | - L Masi
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- CNR Istituto Nazionale Ottica, 50019 Sesto Fiorentino, Italy
| | - C Mazzinghi
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - L Wolswijk
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - F Minardi
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- CNR Istituto Nazionale Ottica, 50019 Sesto Fiorentino, Italy
- Dipartimento di Fisica e Astronomia, Università di Bologna, 40127 Bologna, Italy
| | - M Modugno
- Departamento de Física Teórica e Historia de la Ciencia, Universidad del Pais Vasco UPV/EHU, 48080 Bilbao, Spain
- IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain
| | - G Modugno
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- CNR Istituto Nazionale Ottica, 50019 Sesto Fiorentino, Italy
| | - M Inguscio
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- CNR Istituto Nazionale Ottica, 50019 Sesto Fiorentino, Italy
| | - M Fattori
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
- CNR Istituto Nazionale Ottica, 50019 Sesto Fiorentino, Italy
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10
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Burchianti A, Scazza F, Amico A, Valtolina G, Seman JA, Fort C, Zaccanti M, Inguscio M, Roati G. Connecting Dissipation and Phase Slips in a Josephson Junction between Fermionic Superfluids. Phys Rev Lett 2018; 120:025302. [PMID: 29376686 DOI: 10.1103/physrevlett.120.025302] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Indexed: 06/07/2023]
Abstract
We study the emergence of dissipation in an atomic Josephson junction between weakly coupled superfluid Fermi gases. We find that vortex-induced phase slippage is the dominant microscopic source of dissipation across the Bose-Einstein condensate-Bardeen-Cooper-Schrieffer crossover. We explore different dynamical regimes by tuning the bias chemical potential between the two superfluid reservoirs. For small excitations, we observe dissipation and phase coherence to coexist, with a resistive current followed by well-defined Josephson oscillations. We link the junction transport properties to the phase-slippage mechanism, finding that vortex nucleation is primarily responsible for the observed trends of conductance and critical current. For large excitations, we observe the irreversible loss of coherence between the two superfluids, and transport cannot be described only within an uncorrelated phase-slip picture. Our findings open new directions for investigating the interplay between dissipative and superfluid transport in strongly correlated Fermi systems, and general concepts in out-of-equilibrium quantum systems.
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Affiliation(s)
- A Burchianti
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - F Scazza
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - A Amico
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - G Valtolina
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - J A Seman
- Instituto de Fisica, Universidad Nacional Autónoma de México, 01000 Ciudad de México, Mexico
| | - C Fort
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - M Zaccanti
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - M Inguscio
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - G Roati
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
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11
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Insero G, Borri S, Calonico D, Pastor PC, Clivati C, D'Ambrosio D, De Natale P, Inguscio M, Levi F, Santambrogio G. Measuring molecular frequencies in the 1-10 μm range at 11-digits accuracy. Sci Rep 2017; 7:12780. [PMID: 28986590 PMCID: PMC5630624 DOI: 10.1038/s41598-017-12891-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 09/08/2017] [Indexed: 11/09/2022] Open
Abstract
High-resolution spectroscopy in the 1-10 μm region has never been fully tackled for the lack of widely-tunable and practical light sources. Indeed, all solutions proposed thus far suffer from at least one of three issues: they are feasible only in a narrow spectral range; the power available for spectroscopy is limited; the frequency accuracy is poor. Here, we present a setup for high-resolution spectroscopy, whose approach can be applied in the whole 1-10 μm range. It combines the power of quantum cascade lasers (QCLs) and the accuracy achievable by difference frequency generation using an orientation patterned GaP crystal. The frequency is measured against a primary frequency standard using the Italian metrological fibre link network. We demonstrate the performance of the setup by measuring a vibrational transition in a highly-excited metastable state of CO around 6 μm with 11 digits of precision.
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Affiliation(s)
- G Insero
- Istituto Nazionale di Ottica-CNR & Dipartimento di Fisica e Astronomia, Università di Firenze & European Laboratory for Non-Linear Spectroscopy LENS, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy.,INFN, Istituto Nazionale di Fisica Nucleare, Sez. di Firenze, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy
| | - S Borri
- Istituto Nazionale di Ottica-CNR & Dipartimento di Fisica e Astronomia, Università di Firenze & European Laboratory for Non-Linear Spectroscopy LENS, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy.,INFN, Istituto Nazionale di Fisica Nucleare, Sez. di Firenze, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy
| | - D Calonico
- Istituto Nazionale di Ricerca Metrologica INRIM, Strada delle Cacce 91, 10135, Torino, Italy
| | - P Cancio Pastor
- Istituto Nazionale di Ottica-CNR & Dipartimento di Fisica e Astronomia, Università di Firenze & European Laboratory for Non-Linear Spectroscopy LENS, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy
| | - C Clivati
- Istituto Nazionale di Ricerca Metrologica INRIM, Strada delle Cacce 91, 10135, Torino, Italy
| | - D D'Ambrosio
- Istituto Nazionale di Ottica-CNR & Dipartimento di Fisica e Astronomia, Università di Firenze & European Laboratory for Non-Linear Spectroscopy LENS, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy
| | - P De Natale
- Istituto Nazionale di Ottica-CNR & Dipartimento di Fisica e Astronomia, Università di Firenze & European Laboratory for Non-Linear Spectroscopy LENS, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy.,INFN, Istituto Nazionale di Fisica Nucleare, Sez. di Firenze, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy
| | - M Inguscio
- Istituto Nazionale di Ottica-CNR & Dipartimento di Fisica e Astronomia, Università di Firenze & European Laboratory for Non-Linear Spectroscopy LENS, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy
| | - F Levi
- Istituto Nazionale di Ricerca Metrologica INRIM, Strada delle Cacce 91, 10135, Torino, Italy
| | - G Santambrogio
- Istituto Nazionale di Ottica-CNR & Dipartimento di Fisica e Astronomia, Università di Firenze & European Laboratory for Non-Linear Spectroscopy LENS, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy. .,INFN, Istituto Nazionale di Fisica Nucleare, Sez. di Firenze, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy. .,Istituto Nazionale di Ricerca Metrologica INRIM, Strada delle Cacce 91, 10135, Torino, Italy.
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12
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Scazza F, Valtolina G, Massignan P, Recati A, Amico A, Burchianti A, Fort C, Inguscio M, Zaccanti M, Roati G. Repulsive Fermi Polarons in a Resonant Mixture of Ultracold ^{6}Li Atoms. Phys Rev Lett 2017; 118:083602. [PMID: 28282175 DOI: 10.1103/physrevlett.118.083602] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Indexed: 06/06/2023]
Abstract
We employ radio-frequency spectroscopy to investigate a polarized spin mixture of ultracold ^{6}Li atoms close to a broad Feshbach scattering resonance. Focusing on the regime of strong repulsive interactions, we observe well-defined coherent quasiparticles even for unitarity-limited interactions. We characterize the many-body system by extracting the key properties of repulsive Fermi polarons: the energy E_{+}, the effective mass m^{*}, the residue Z, and the decay rate Γ. Above a critical interaction, E_{+} is found to exceed the Fermi energy of the bath, while m^{*} diverges and even turns negative, thereby indicating that the repulsive Fermi liquid state becomes energetically and thermodynamically unstable.
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Affiliation(s)
- F Scazza
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - G Valtolina
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - P Massignan
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels, Spain
| | - A Recati
- INO-CNR BEC Center and Dipartimento di Fisica, Università di Trento, 38123 Povo, Italy
- Ludwig-Maximilians-Universität München, 80333 München, Germany
| | - A Amico
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - A Burchianti
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - C Fort
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - M Inguscio
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - M Zaccanti
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - G Roati
- Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche (INO-CNR), 50019 Sesto Fiorentino, Italy
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
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13
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Livi LF, Cappellini G, Diem M, Franchi L, Clivati C, Frittelli M, Levi F, Calonico D, Catani J, Inguscio M, Fallani L. Synthetic Dimensions and Spin-Orbit Coupling with an Optical Clock Transition. Phys Rev Lett 2016; 117:220401. [PMID: 27925719 DOI: 10.1103/physrevlett.117.220401] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Indexed: 06/06/2023]
Abstract
We demonstrate a novel way of synthesizing spin-orbit interactions in ultracold quantum gases, based on a single-photon optical clock transition coupling two long-lived electronic states of two-electron ^{173}Yb atoms. By mapping the electronic states onto effective sites along a synthetic "electronic" dimension, we have engineered fermionic ladders with synthetic magnetic flux in an experimental configuration that has allowed us to achieve uniform fluxes on a lattice with minimal requirements and unprecedented tunability. We have detected the spin-orbit coupling with fiber-link-enhanced clock spectroscopy and directly measured the emergence of chiral edge currents, probing them as a function of the flux. These results open new directions for the investigation of topological states of matter with ultracold atomic gases.
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Affiliation(s)
- L F Livi
- LENS European Laboratory for Nonlinear Spectroscopy, I-50019 Sesto Fiorentino, Italy
- INO-CNR Istituto Nazionale di Ottica del CNR, Sezione di Sesto Fiorentino, I-50019 Sesto Fiorentino, Italy
| | - G Cappellini
- Department of Physics and Astronomy, University of Florence, I-50019 Sesto Fiorentino, Italy
- INO-CNR Istituto Nazionale di Ottica del CNR, Sezione di Sesto Fiorentino, I-50019 Sesto Fiorentino, Italy
| | - M Diem
- ILP Institut für Laserphysik, Universität Hamburg, D-20355 Hamburg, Germany
- INRIM Istituto Nazionale di Ricerca Metrologica, I-10135 Torino, Italy
| | - L Franchi
- Department of Physics and Astronomy, University of Florence, I-50019 Sesto Fiorentino, Italy
| | - C Clivati
- INRIM Istituto Nazionale di Ricerca Metrologica, I-10135 Torino, Italy
| | - M Frittelli
- INRIM Istituto Nazionale di Ricerca Metrologica, I-10135 Torino, Italy
| | - F Levi
- INRIM Istituto Nazionale di Ricerca Metrologica, I-10135 Torino, Italy
| | - D Calonico
- INRIM Istituto Nazionale di Ricerca Metrologica, I-10135 Torino, Italy
| | - J Catani
- LENS European Laboratory for Nonlinear Spectroscopy, I-50019 Sesto Fiorentino, Italy
- INO-CNR Istituto Nazionale di Ottica del CNR, Sezione di Sesto Fiorentino, I-50019 Sesto Fiorentino, Italy
- INFN Istituto Nazionale di Fisica Nucleare, Sezione di Firenze, I-50019 Sesto Fiorentino, Italy
| | - M Inguscio
- LENS European Laboratory for Nonlinear Spectroscopy, I-50019 Sesto Fiorentino, Italy
- Department of Physics and Astronomy, University of Florence, I-50019 Sesto Fiorentino, Italy
- INO-CNR Istituto Nazionale di Ottica del CNR, Sezione di Sesto Fiorentino, I-50019 Sesto Fiorentino, Italy
| | - L Fallani
- LENS European Laboratory for Nonlinear Spectroscopy, I-50019 Sesto Fiorentino, Italy
- Department of Physics and Astronomy, University of Florence, I-50019 Sesto Fiorentino, Italy
- INO-CNR Istituto Nazionale di Ottica del CNR, Sezione di Sesto Fiorentino, I-50019 Sesto Fiorentino, Italy
- INFN Istituto Nazionale di Fisica Nucleare, Sezione di Firenze, I-50019 Sesto Fiorentino, Italy
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14
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Trenkwalder A, Spagnolli G, Semeghini G, Coop S, Landini M, Castilho P, Pezzè L, Modugno G, Inguscio M, Smerzi A, Fattori M. Quantum Phase Transitions with Parity-Symmetry Breaking and Hysteresis. Nat Phys 2016; 12:826-829. [PMID: 27610189 PMCID: PMC5011422 DOI: 10.1038/nphys3743] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 03/24/2016] [Indexed: 06/02/2023]
Abstract
Symmetry-breaking quantum phase transitions play a key role in several condensed matter, cosmology and nuclear physics theoretical models1-3. Its observation in real systems is often hampered by finite temperatures and limited control of the system parameters. In this work we report for the first time the experimental observation of the full quantum phase diagram across a transition where the spatial parity symmetry is broken. Our system is made of an ultra-cold gas with tunable attractive interactions trapped in a spatially symmetric double-well potential. At a critical value of the interaction strength, we observe a continuous quantum phase transition where the gas spontaneously localizes in one well or the other, thus breaking the underlying symmetry of the system. Furthermore, we show the robustness of the asymmetric state against controlled energy mismatch between the two wells. This is the result of hysteresis associated with an additional discontinuous quantum phase transition that we fully characterize. Our results pave the way to the study of quantum critical phenomena at finite temperature4, the investigation of macroscopic quantum tunneling of the order parameter in the hysteretic regime and the production of strongly quantum entangled states at critical points5.
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Affiliation(s)
- A Trenkwalder
- Istituto Nazionale di Ottica-CNR, 50019 Sesto Fiorentino, Italy
| | - G Spagnolli
- LENS European Laboratory for Nonlinear Spectroscopy, and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - G Semeghini
- LENS European Laboratory for Nonlinear Spectroscopy, and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - S Coop
- LENS European Laboratory for Nonlinear Spectroscopy, and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy; ICFO-Institut de Ciencies Fotoniques, Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain
| | - M Landini
- Istituto Nazionale di Ottica-CNR, 50019 Sesto Fiorentino, Italy
| | - P Castilho
- Istituto Nazionale di Ottica-CNR, 50019 Sesto Fiorentino, Italy; Instituto de Física de São Carlos, Universidade de São Paulo, C.P. 369, 13560-970, São Carlos, São Paulo, Brazil
| | - L Pezzè
- Istituto Nazionale di Ottica-CNR, 50019 Sesto Fiorentino, Italy; LENS European Laboratory for Nonlinear Spectroscopy, and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy; Quantum Science and Technology in Arcetri, QSTAR, 50125 Firenze, Italy
| | - G Modugno
- LENS European Laboratory for Nonlinear Spectroscopy, and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - M Inguscio
- Istituto Nazionale di Ottica-CNR, 50019 Sesto Fiorentino, Italy; LENS European Laboratory for Nonlinear Spectroscopy, and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
| | - A Smerzi
- Istituto Nazionale di Ottica-CNR, 50019 Sesto Fiorentino, Italy; LENS European Laboratory for Nonlinear Spectroscopy, and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy; Quantum Science and Technology in Arcetri, QSTAR, 50125 Firenze, Italy
| | - M Fattori
- Istituto Nazionale di Ottica-CNR, 50019 Sesto Fiorentino, Italy; LENS European Laboratory for Nonlinear Spectroscopy, and Dipartimento di Fisica e Astronomia, Università di Firenze, 50019 Sesto Fiorentino, Italy
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15
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Pagano G, Mancini M, Cappellini G, Livi L, Sias C, Catani J, Inguscio M, Fallani L. Strongly Interacting Gas of Two-Electron Fermions at an Orbital Feshbach Resonance. Phys Rev Lett 2015; 115:265301. [PMID: 26764999 DOI: 10.1103/physrevlett.115.265301] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Indexed: 06/05/2023]
Abstract
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 (173)Yb 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.
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Affiliation(s)
- G Pagano
- Department of Physics and Astronomy, University of Florence, I-50019 Sesto Fiorentino, Italy
| | - M Mancini
- Department of Physics and Astronomy, University of Florence, I-50019 Sesto Fiorentino, Italy
| | - G Cappellini
- LENS European Laboratory for Nonlinear Spectroscopy, I-50019 Sesto Fiorentino, Italy
| | - L Livi
- LENS European Laboratory for Nonlinear Spectroscopy, I-50019 Sesto Fiorentino, Italy
| | - C Sias
- LENS European Laboratory for Nonlinear Spectroscopy, I-50019 Sesto Fiorentino, Italy
- INRIM Istituto Nazionale di Ricerca Metrologica, I-10135 Torino, Italy
| | - J Catani
- LENS European Laboratory for Nonlinear Spectroscopy, I-50019 Sesto Fiorentino, Italy
- INO-CNR Istituto Nazionale di Ottica del CNR, Sezione di Sesto Fiorentino, I-50019 Sesto Fiorentino, Italy
- INFN Istituto Nazionale di Fisica Nucleare, Sezione di Firenze, I-50019 Sesto Fiorentino, Italy
| | - M Inguscio
- Department of Physics and Astronomy, University of Florence, I-50019 Sesto Fiorentino, Italy
- LENS European Laboratory for Nonlinear Spectroscopy, I-50019 Sesto Fiorentino, Italy
- INRIM Istituto Nazionale di Ricerca Metrologica, I-10135 Torino, Italy
| | - L Fallani
- Department of Physics and Astronomy, University of Florence, I-50019 Sesto Fiorentino, Italy
- LENS European Laboratory for Nonlinear Spectroscopy, I-50019 Sesto Fiorentino, Italy
- INFN Istituto Nazionale di Fisica Nucleare, Sezione di Firenze, I-50019 Sesto Fiorentino, Italy
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16
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Valtolina G, Burchianti A, Amico A, Neri E, Xhani K, Seman JA, Trombettoni A, Smerzi A, Zaccanti M, Inguscio M, Roati G. Josephson effect in fermionic superfluids across the BEC-BCS crossover. Science 2015; 350:1505-8. [DOI: 10.1126/science.aac9725] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 11/13/2015] [Indexed: 11/02/2022]
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17
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Mancini M, Pagano G, Cappellini G, Livi L, Rider M, Catani J, Sias C, Zoller P, Inguscio M, Dalmonte M, Fallani L. Observation of chiral edge states with neutral fermions in synthetic Hall ribbons. Science 2015; 349:1510-3. [DOI: 10.1126/science.aaa8736] [Citation(s) in RCA: 466] [Impact Index Per Article: 51.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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18
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Cappellini G, Mancini M, Pagano G, Lombardi P, Livi L, Siciliani de Cumis M, Cancio P, Pizzocaro M, Calonico D, Levi F, Sias C, Catani J, Inguscio M, Fallani L. Direct observation of coherent interorbital spin-exchange dynamics. Phys Rev Lett 2014; 113:120402. [PMID: 25279608 DOI: 10.1103/physrevlett.113.120402] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Indexed: 06/03/2023]
Abstract
We report on the first direct observation of fast spin-exchange coherent oscillations between different long-lived electronic orbitals of ultracold 173Yb fermions. We measure, in a model-independent way, the strength of the exchange interaction driving this coherent process. This observation allows us to retrieve important information on the interorbital collisional properties of 173Yb atoms and paves the way to novel quantum simulations of paradigmatic models of two-orbital quantum magnetism.
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Affiliation(s)
- G Cappellini
- LENS European Laboratory for Nonlinear Spectroscopy, Sesto Fiorentino 50019, Italy and INO-CNR Istituto Nazionale di Ottica del CNR, Sezione di Sesto Fiorentino, Sesto Fiorentino 50019, Italy
| | - M Mancini
- Department of Physics and Astronomy, University of Florence, Sesto Fiorentino 50019, Italy and INO-CNR Istituto Nazionale di Ottica del CNR, Sezione di Sesto Fiorentino, Sesto Fiorentino 50019, Italy
| | - G Pagano
- INO-CNR Istituto Nazionale di Ottica del CNR, Sezione di Sesto Fiorentino, Sesto Fiorentino 50019, Italy and Scuola Normale Superiore di Pisa, Pisa 56126, Italy
| | - P Lombardi
- LENS European Laboratory for Nonlinear Spectroscopy, Sesto Fiorentino 50019, Italy
| | - L Livi
- Department of Physics and Astronomy, University of Florence, Sesto Fiorentino 50019, Italy
| | - M Siciliani de Cumis
- INO-CNR Istituto Nazionale di Ottica del CNR, Sezione di Sesto Fiorentino, Sesto Fiorentino 50019, Italy
| | - P Cancio
- LENS European Laboratory for Nonlinear Spectroscopy, Sesto Fiorentino 50019, Italy and Department of Physics and Astronomy, University of Florence, Sesto Fiorentino 50019, Italy and INO-CNR Istituto Nazionale di Ottica del CNR, Sezione di Sesto Fiorentino, Sesto Fiorentino 50019, Italy
| | - M Pizzocaro
- INRIM Istituto Nazionale di Ricerca Metrologica, Torino 10135, Italy
| | - D Calonico
- INRIM Istituto Nazionale di Ricerca Metrologica, Torino 10135, Italy
| | - F Levi
- INRIM Istituto Nazionale di Ricerca Metrologica, Torino 10135, Italy
| | - C Sias
- LENS European Laboratory for Nonlinear Spectroscopy, Sesto Fiorentino 50019, Italy and INO-CNR Istituto Nazionale di Ottica del CNR, Sezione di Sesto Fiorentino, Sesto Fiorentino 50019, Italy
| | - J Catani
- LENS European Laboratory for Nonlinear Spectroscopy, Sesto Fiorentino 50019, Italy and INO-CNR Istituto Nazionale di Ottica del CNR, Sezione di Sesto Fiorentino, Sesto Fiorentino 50019, Italy
| | - M Inguscio
- LENS European Laboratory for Nonlinear Spectroscopy, Sesto Fiorentino 50019, Italy and Department of Physics and Astronomy, University of Florence, Sesto Fiorentino 50019, Italy and INRIM Istituto Nazionale di Ricerca Metrologica, Torino 10135, Italy
| | - L Fallani
- LENS European Laboratory for Nonlinear Spectroscopy, Sesto Fiorentino 50019, Italy and Department of Physics and Astronomy, University of Florence, Sesto Fiorentino 50019, Italy and INO-CNR Istituto Nazionale di Ottica del CNR, Sezione di Sesto Fiorentino, Sesto Fiorentino 50019, Italy
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19
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Lucioni E, Tanzi L, D'Errico C, Moratti M, Inguscio M, Modugno G. Modeling the transport of interacting matter waves in a disordered system by a nonlinear diffusion equation. Phys Rev E Stat Nonlin Soft Matter Phys 2013; 87:042922. [PMID: 23679504 DOI: 10.1103/physreve.87.042922] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Indexed: 06/02/2023]
Abstract
We model the expansion of an interacting atomic Bose-Einstein condensate in a disordered lattice with a nonlinear diffusion equation normally used for a variety of classical systems. We find approximate solutions of the diffusion equation that well reproduce the experimental observations for both short and asymptotic expansion times. Our study establishes a connection between the peculiar shape of the expanding density profiles and the microscopic nonlinear diffusion coefficients.
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Affiliation(s)
- E Lucioni
- LENS and Dipartimento di Fisica e Astronomia, Universitá di Firenze, and INO-CNR, 50019 Sesto Fiorentino, Italy
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Fabbri N, Huber SD, Clément D, Fallani L, Fort C, Inguscio M, Altman E. Quasiparticle dynamics in a bose insulator probed by interband bragg spectroscopy. Phys Rev Lett 2012; 109:055301. [PMID: 23006183 DOI: 10.1103/physrevlett.109.055301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Revised: 04/30/2012] [Indexed: 06/01/2023]
Abstract
We investigate experimentally and theoretically the dynamical properties of a Mott insulator in decoupled one-dimensional chains. Using a theoretical analysis of the Bragg excitation scheme, we show that the spectrum of interband transitions holds information on the single-particle Green's function of the insulator. In particular, the existence of particle-hole coherence due to quantum fluctuations in the Mott state is clearly seen in the Bragg spectra and quantified. Finally, we propose a scheme to directly measure the full, momentum-resolved spectral function as obtained in the angle-resolved photoemission spectroscopy of solids.
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Affiliation(s)
- N Fabbri
- LENS, Dipartimento di Fisica e Astronomia, Università di Firenze, Sesto Fiorentino, Italy.
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21
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Cancio Pastor P, Consolino L, Giusfredi G, De Natale P, Inguscio M, Yerokhin VA, Pachucki K. Frequency metrology of helium around 1083 nm and determination of the nuclear charge radius. Phys Rev Lett 2012; 108:143001. [PMID: 22540790 DOI: 10.1103/physrevlett.108.143001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2011] [Revised: 02/29/2012] [Indexed: 05/31/2023]
Abstract
We measure the absolute frequency of seven out of the nine allowed transitions between the 2 (3)S and 2 (3)P hyperfine manifolds in a metastable (3)He beam by using an optical frequency comb synthesizer-assisted spectrometer. The relative uncertainty of our measurements ranges from 1×10(-11) to 5×10(-12), which is, to our knowledge, the most precise result for any optical ^{3}He transition to date. The resulting 2 (3)P-2 (3)S centroid frequency is 276,702,827,204.8(2.4) kHz. Comparing this value with the known result for the (4)He centroid and performing ab initio QED calculations of the (4)He-(3)He isotope shift, we extract the difference of the squared nuclear charge radii δr(2) of (3)He and (4)He. Our result for δr(2)=1.074(3) fm(2) disagrees by about 4σ with the recent determination [R. van Rooij et al., Science 333, 196 (2011)].
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Affiliation(s)
- P Cancio Pastor
- Istituto Nazionale di Ottica-CNR (INO-CNR), Via Nello Carrara 1, I-50019 Sesto Fiorentino, Italy.
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22
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Sardi F, Fassina L, Venturini L, Inguscio M, Guerriero F, Rolfo E, Ricevuti G. Alzheimer's disease, autoimmunity and inflammation. The good, the bad and the ugly. Autoimmun Rev 2011; 11:149-53. [DOI: 10.1016/j.autrev.2011.09.005] [Citation(s) in RCA: 122] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Accepted: 09/19/2011] [Indexed: 11/26/2022]
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23
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Lucioni E, Deissler B, Tanzi L, Roati G, Zaccanti M, Modugno M, Larcher M, Dalfovo F, Inguscio M, Modugno G. Observation of subdiffusion in a disordered interacting system. Phys Rev Lett 2011; 106:230403. [PMID: 21770486 DOI: 10.1103/physrevlett.106.230403] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 04/21/2011] [Indexed: 05/31/2023]
Abstract
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 absence of atom-atom interaction shows instead a slow expansion with a subdiffusive behavior when a controlled repulsive interaction is added. The measured features of the subdiffusion are compared to numerical simulations and a heuristic model. The observations confirm the nature of subdiffusion as interaction-assisted hopping between localized states and highlight a role of the spatial correlation of the disorder.
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Affiliation(s)
- E Lucioni
- LENS and Dipartimento di Fisica e Astronomia, Università di Firenze, and INO-CNR, Sesto Fiorentino, Italy.
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24
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Consolino L, Giusfredi G, De Natale P, Inguscio M, Cancio P. Optical frequency comb assisted laser system for multiplex precision spectroscopy. Opt Express 2011; 19:3155-3162. [PMID: 21369137 DOI: 10.1364/oe.19.003155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A laser system composed of two lasers phase-locked onto an Optical Frequency Comb Synthesizer (OFCS), operating around 1083 nm, was developed. An absolute frequency precision of 6x10(-13) at 1s, limited by the OFCS, was measured with a residual rms phase-noise of 71 mrad and 87 mrad for the two phase-locks, respectively. Multiplex spectroscopy on 1083 nm Helium transitions with this set-up is demonstrated. Generalization of this system to a larger number of OFCS assisted laser sources for wider frequency separations, even in other spectral regions, is discussed.
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Affiliation(s)
- L Consolino
- European Laboratory for Non-Linear Spectroscopy (LENS) and Dipartimento di Fisica,Universitá degli Studi di Firenze, Via N. Carrara 1, 50019-Sesto Fiorentino (FI), Italy.
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25
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Lamporesi G, Catani J, Barontini G, Nishida Y, Inguscio M, Minardi F. Scattering in mixed dimensions with ultracold gases. Phys Rev Lett 2010; 104:153202. [PMID: 20481985 DOI: 10.1103/physrevlett.104.153202] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Indexed: 05/29/2023]
Abstract
We experimentally investigate the mix-dimensional scattering occurring when the collisional partners live in different dimensions. We employ a binary mixture of ultracold atoms and exploit a species-selective 1D optical lattice to confine only one atomic species in 2D. By applying an external magnetic field in proximity of a Feshbach resonance, we adjust the free-space scattering length to observe a series of resonances in mixed dimensions. By monitoring 3-body inelastic losses, we measure the magnetic field values corresponding to the mix-dimensional scattering resonances and find a good agreement with the theoretical predictions based on simple energy considerations.
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Affiliation(s)
- G Lamporesi
- European Laboratory for Nonlinear Spectroscopy and Dipartimento di Fisica, Università di Firenze, via Nello Carrara 1, I-50019 Sesto Fiorentino, Italy
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26
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Luppi C, Fioravanti M, Bertolini B, Inguscio M, Grugnetti A, Guerriero F, Rovelli C, Cantoni F, Guagnano P, Marazzi E, Rolfo E, Ghianda D, Levante D, Guerrini C, Bonacasa R, Solerte SB. Growth factors decrease in subjects with mild to moderate Alzheimer's disease (AD): potential correction with dehydroepiandrosterone-sulphate (DHEAS). Arch Gerontol Geriatr 2010; 49 Suppl 1:173-84. [PMID: 19836631 DOI: 10.1016/j.archger.2009.09.027] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The integrity of neuroprotection is an important component against the development of cognitive disorders and AD. Within this context, DHEAS would seem to have some positive metabolic and endocrine effects to delay brain aging by recovering the impairment of neuroprotective growth factors. In the present study we measured by ELISA the secretion of insulin-like growth factor-1 (IGF-1), vascular endothelial growth factor (VEGF), and transforming growth factor-beta1 (TGFbeta1) in the supernatants of cultured circulating peripheral blood mononuclear cells (PBMC) from which natural killer cells (NK) were separated (PBMC-NK) (pg/ml/7.75x10(6) cells) in healthy subjects and in age-matched patients with mild to moderate AD. The growth factors were measured in spontaneous conditions and after stimulation with growth hormone (GH) 1 microg/ml (IGF-1), lipopolysaccharide (LPS) 1 microg/ml (VEGF) and glucose 10 microM (TGF(beta1). AD group demonstrated at baseline a severe reduction of IGF-1 (3.7+1.2 pg/ml after GH), VEGF (63+/-18 pg/ml spontaneous and 210+/-65 pg/ml after LPS) and TGF(beta1 (33+/-10 pg/ml spontaneous and 75+/-12 pg/ml after glucose) secretions compared to healthy elderly subjects (IGF-1, 9.5+/-2.8 pg/ml after GH, p<0.001; VEGF, 117+/-38 pg/ml spontaneous, p<0.001 and 690+/-120 pg/ml after LPS, p<0.001; and TGF(beta1, 73+/-21 pg/ml spontaneous, p<0.001 and 169+/-53 pg/ml after glucose, p<0.001). Significant positive correlations between IGF-1 and VEGF concentrations were found both in healthy subjects (r=0.87, p<0.001) and in AD subjects (r=0.87, p<0.001). The co-incubation of NK cells with DHEAS (10(6) M/ml/cells) significantly increase IGF-1, VEGF and TGF (beta1 production, reaching in AD group the normal concentrations found in healthy subjects (IGF-1, 7.9 + 2.4 pg/ml after GH; VEGF, 105+/-31 pg/ml spontaneous and 670+/-112 pg/ml after LPS; and TGFfbeta1, 68+/-18 pg/ml spontaneous and 155+/-48 pg/ml after glucose). These data suggested that DHEAS is able to increase the immunoendocrine production of neuroprotective growth factors, which is reduced in AD subjects, so suggesting a new approach in the treatment of dementia.
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Affiliation(s)
- C Luppi
- Department of Internal Medicine, School of Geriatrics, University of Pavia, Pavia, Italy
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27
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Catani J, Barontini G, Lamporesi G, Rabatti F, Thalhammer G, Minardi F, Stringari S, Inguscio M. Entropy exchange in a mixture of ultracold atoms. Phys Rev Lett 2009; 103:140401. [PMID: 19905548 DOI: 10.1103/physrevlett.103.140401] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2009] [Revised: 07/16/2009] [Indexed: 05/28/2023]
Abstract
We investigate experimentally the entropy transfer between two distinguishable atomic quantum gases at ultralow temperatures. Exploiting a species-selective trapping potential, we are able to control the entropy of one target gas in presence of a second auxiliary gas. With this method, we drive the target gas into the degenerate regime in conditions of controlled temperature by transferring entropy to the auxiliary gas. We envision that our method could be useful both to achieve the low entropies required to realize new quantum phases and to measure the temperature of atoms in deep optical lattices. We verified the thermalization of the two species in a 1D lattice.
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Affiliation(s)
- J Catani
- LENS-European Laboratory for Non-Linear Spectroscopy and Dipartimento di Fisica, Università di Firenze, via N. Carrara 1, I-50019 Sesto Fiorentino-Firenze, Italy
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28
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Barontini G, Weber C, Rabatti F, Catani J, Thalhammer G, Inguscio M, Minardi F. Observation of heteronuclear atomic Efimov resonances. Phys Rev Lett 2009; 103:043201. [PMID: 19659348 DOI: 10.1103/physrevlett.103.043201] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2009] [Indexed: 05/28/2023]
Abstract
Building on the recent experimental observation with ultracold atoms, we report the first experimental evidence of Efimov physics in a heteronuclear system. A mixture of ;{41}K and ;{87}Rb atoms was cooled to few hundred nanokelvins and stored in an optical dipole trap. Exploiting a broad interspecies Feshbach resonance, the losses due to three-body collisions were studied as a function of the interspecies scattering length. We observe an enhancement of the three-body collisions for three distinct values of the interspecies scattering lengths, both positive and negative, where no Feshbach resonances are expected. We attribute the two features at negative scattering length to the existence of two kinds of Efimov trimers, KKRb and KRbRb.
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Affiliation(s)
- G Barontini
- LENS, European Laboratory for Non-Linear Spectroscopy and Dipartimento di Fisica, Università di Firenze, I-50019 Sesto Fiorentino, Firenze, Italy
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29
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Clément D, Fabbri N, Fallani L, Fort C, Inguscio M. Exploring correlated 1D bose gases from the superfluid to the mott-insulator state by inelastic light scattering. Phys Rev Lett 2009; 102:155301. [PMID: 19518645 DOI: 10.1103/physrevlett.102.155301] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2008] [Revised: 02/10/2009] [Indexed: 05/27/2023]
Abstract
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.
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Affiliation(s)
- D Clément
- LENS, Dipartimento di Fisica, Università di Firenze and INFM-CNR, I-50019 Sesto Fiorentino (FI), Italy
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30
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Affiliation(s)
- L Fallani
- LENS European Laboratory for Nonlinear Spectroscopy, Dipartimento di Fisica, University of Florence, and INFMCNR, Via Nello Carrara 1, I-50019 Sesto Fiorentino (FI), Italy.
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31
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Fattori M, Roati G, Deissler B, D'Errico C, Zaccanti M, Jona-Lasinio M, Santos L, Inguscio M, Modugno G. Magnetic dipolar interaction in a Bose-Einstein condensate atomic interferometer. Phys Rev Lett 2008; 101:190405. [PMID: 19113248 DOI: 10.1103/physrevlett.101.190405] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Indexed: 05/27/2023]
Abstract
We study the role played by the magnetic dipole interaction in the decoherence of a lattice-based interferometer that employs an alkali Bose-Einstein condensate with a tunable scattering length. The different behavior we observe for two different orientations of the dipoles gives us evidence of the anisotropic character of the interaction. The experiment is correctly reproduced by a model we develop only if the long-range interaction between different lattice sites is taken into account. Our model indicates that dipolar interaction can be compensated by a proper choice of the scattering length and that the magnetic dipole interaction should not represent an obstacle for atom interferometry with Bose-Einstein condensates with a tunable interaction.
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Affiliation(s)
- M Fattori
- LENS and Dipartimento di Fisica, Università di Firenze, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy.
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32
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Guarrera V, Fabbri N, Fallani L, Fort C, van der Stam KMR, Inguscio M. Noise correlation spectroscopy of the broken order of a Mott insulating phase. Phys Rev Lett 2008; 100:250403. [PMID: 18643641 DOI: 10.1103/physrevlett.100.250403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2008] [Revised: 05/06/2008] [Indexed: 05/26/2023]
Abstract
We use a two-color lattice to break the homogeneous site occupation of an atomic Mott insulator of bosonic 87Rb. We detect the disruption of the ordered Mott domains via noise correlation analysis of the atomic density distribution after time of flight. The appearance of additional correlation peaks evidences the redistribution of the atoms into a strongly inhomogeneous insulating state, in quantitative agreement with the predictions.
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Affiliation(s)
- V Guarrera
- LENS European Laboratory for Nonlinear Spectroscopy and Dipartimento di Fisica, Università di Firenze, via Nello Carrara 1, I-50019 Sesto Fiorentino (FI), Italy
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33
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Thalhammer G, Barontini G, De Sarlo L, Catani J, Minardi F, Inguscio M. Double species Bose-Einstein condensate with tunable interspecies interactions. Phys Rev Lett 2008; 100:210402. [PMID: 18518587 DOI: 10.1103/physrevlett.100.210402] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2008] [Indexed: 05/26/2023]
Abstract
We produce Bose-Einstein condensates of two different species, 87Rb and 41K, in an optical dipole trap in proximity of interspecies Feshbach resonances. We discover and characterize two Feshbach resonances, located around 35 and 79 G, by observing the three-body losses and the elastic cross section. The narrower resonance is exploited to create a double species condensate with tunable interactions. Our system opens the way to the exploration of double species Mott insulators and, more in general, of the quantum phase diagram of the two-species Bose-Hubbard model.
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Affiliation(s)
- G Thalhammer
- LENS - European Laboratory for Non-Linear Spectroscopy and Dipartimento di Fisica, Università di Firenze, via N. Carrara 1, I-50019 Sesto Fiorentino - Firenze, Italy
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34
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Fattori M, D'Errico C, Roati G, Zaccanti M, Jona-Lasinio M, Modugno M, Inguscio M, Modugno G. Atom interferometry with a weakly interacting Bose-Einstein condensate. Phys Rev Lett 2008; 100:080405. [PMID: 18352607 DOI: 10.1103/physrevlett.100.080405] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2007] [Indexed: 05/26/2023]
Abstract
We demonstrate the operation of an atom interferometer based on a weakly interacting Bose-Einstein condensate. We strongly reduce the interaction induced decoherence that usually limits interferometers based on trapped condensates by tuning the s-wave scattering length almost to zero via a magnetic Feshbach resonance. We employ a 39K condensate trapped in an optical lattice, where Bloch oscillations are forced by gravity. The fine-tuning of the scattering length down to 0.1 a_(0) and the micrometric sizes of the atomic sample make our system a very promising candidate for measuring forces with high spatial resolution. Our technique can be in principle extended to other measurement schemes opening new possibilities in the field of trapped atom interferometry.
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Affiliation(s)
- M Fattori
- Dipartimento di Fisica, Università di Firenze, and INFM-CNR Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
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35
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Roati G, Zaccanti M, D'Errico C, Catani J, Modugno M, Simoni A, Inguscio M, Modugno G. 39K Bose-Einstein condensate with tunable interactions. Phys Rev Lett 2007; 99:010403. [PMID: 17678142 DOI: 10.1103/physrevlett.99.010403] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Indexed: 05/16/2023]
Abstract
We produce a Bose-Einstein condensate of 39K atoms. Condensation of this species with a naturally small and negative scattering length is achieved by a combination of sympathetic cooling with 87Rb and direct evaporation, exploiting the magnetic tuning of both inter- and intraspecies interactions at Feshbach resonances. We explore the tunability of the self-interactions by studying the expansion and the stability of the condensate. We find that a 39K condensate is interesting for future experiments requiring a weakly-interacting Bose gas.
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Affiliation(s)
- G Roati
- LENS and Dipartimento di Fisica, Università di Firenze, INFN and CNR-INFM, 50019 Sesto Fiorentino, Italy
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36
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Fallani L, Lye JE, Guarrera V, Fort C, Inguscio M. Ultracold atoms in a disordered crystal of light: towards a bose glass. Phys Rev Lett 2007; 98:130404. [PMID: 17501171 DOI: 10.1103/physrevlett.98.130404] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2006] [Indexed: 05/15/2023]
Abstract
We use a bichromatic optical lattice to experimentally realize a disordered system of ultracold strongly interacting 87Rb bosons. In the absence of disorder, the atoms are pinned by repulsive interactions in the sites of an ideal optical crystal, forming one-dimensional Mott-insulator states. We measure the excitation spectrum of the system as a function of disorder strength and characterize its phase-coherence properties with a time-of-flight technique. Increasing disorder, we observe a broadening of the Mott-insulator resonances and the transition to a state with vanishing long-range phase coherence and a flat density of excitations, which suggest the formation of a Bose-glass phase.
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Affiliation(s)
- L Fallani
- LENS European Laboratory for Nonlinear Spectroscopy and Dipartimento di Fisica, Università di Firenze, via Nello Carrara 1, I-50019 Sesto Fiorentino (FI), Italy.
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37
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Fort C, Fallani L, Guarrera V, Lye JE, Modugno M, Wiersma DS, Inguscio M. Effect of optical disorder and single defects on the expansion of a Bose-Einstein condensate in a one-dimensional waveguide. Phys Rev Lett 2005; 95:170410. [PMID: 16383807 DOI: 10.1103/physrevlett.95.170410] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2005] [Indexed: 05/05/2023]
Abstract
We investigate the one-dimensional expansion of a Bose-Einstein condensate in an optical guide in the presence of a random potential created with optical speckles. With the speckle the expansion of the condensate is strongly inhibited. A detailed investigation has been carried out varying the experimental conditions and checking the expansion when a single optical defect is present. The experimental results are in good agreement with numerical calculations based on the Gross-Pitaevskii equation.
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Affiliation(s)
- C Fort
- LENS, Dipartimento di Fisica and INFM, Università di Firenze, via Nello Carrara 1, I-50019 Sesto Fiorentino (FI), Italy
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38
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Carusotto I, Pitaevskii L, Stringari S, Modugno G, Inguscio M. Sensitive measurement of forces at the micron scale using Bloch oscillations of ultracold atoms. Phys Rev Lett 2005; 95:093202. [PMID: 16197214 DOI: 10.1103/physrevlett.95.093202] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2005] [Indexed: 05/04/2023]
Abstract
We show that Bloch oscillations of ultracold fermionic atoms in the periodic potential of an optical lattice can be used for a sensitive measurement of forces at the micrometer length scale, e.g., in the vicinity of a dielectric surface. In particular, the proposed approach allows us to perform a local and direct measurement of the Casimir-Polder force which is, for realistic experimental parameters, as large as 10(-4) gravity.
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Affiliation(s)
- I Carusotto
- Istituto Nazionale per Fisica per la Materia BEC-CRS and Dipartimento di Fisica, Universitá di Trento, I-38050 Povo, Italy
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39
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Baggio L, Bignotto M, Bonaldi M, Cerdonio M, Conti L, De Rosa M, Falferi P, Fortini P, Inguscio M, Liguori N, Marin F, Mezzena R, Mion A, Ortolan A, Prodi GA, Poggi S, Salemi F, Soranzo G, Taffarello L, Vedovato G, Vinante A, Vitale S, Zendri JP. Upper limits on gravitational-wave emission in association with the 27 Dec 2004 giant flare of SGR1806-20. Phys Rev Lett 2005; 95:081103. [PMID: 16196848 DOI: 10.1103/physrevlett.95.081103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2005] [Indexed: 05/04/2023]
Abstract
At the time when the giant flare of SGR1806-20 occurred, the AURIGA "bar" gravitational-wave (GW) detector was on the air with a noise performance close to stationary Gaussian. This allows us to set relevant upper limits, at a number of frequencies in the vicinities of 900 Hz, on the amplitude of the damped GW wave trains, which, according to current models, could have been emitted, due to the excitation of normal modes of the star associated with the peak in x-ray luminosity.
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Affiliation(s)
- L Baggio
- Institute for Cosmic Ray Research, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8582, Japan
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40
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Lye JE, Fallani L, Modugno M, Wiersma DS, Fort C, Inguscio M. Bose-Einstein condensate in a random potential. Phys Rev Lett 2005; 95:070401. [PMID: 16196765 DOI: 10.1103/physrevlett.95.070401] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2004] [Indexed: 05/04/2023]
Abstract
An optical speckle potential is used to investigate the static and dynamic properties of a Bose-Einstein condensate in the presence of disorder. With small levels of disorder, stripes are observed in the expanded density profile and strong damping of dipole and quadrupole oscillations is seen. Uncorrelated frequency shifts of the two modes are measured and are explained using a sum-rules approach and by the numerical solution of the Gross-Pitaevskii equation.
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Affiliation(s)
- J E Lye
- LENS, Dipartimento di Fisica, and INFM Università di Firenze, Sesto Fiorentino (FI), Italy.
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41
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Fallani L, De Sarlo L, Lye JE, Modugno M, Saers R, Fort C, Inguscio M. Observation of dynamical instability for a Bose-Einstein condensate in a moving 1D optical lattice. Phys Rev Lett 2004; 93:140406. [PMID: 15524775 DOI: 10.1103/physrevlett.93.140406] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2004] [Indexed: 05/24/2023]
Abstract
We have experimentally studied the unstable dynamics of a harmonically trapped Bose-Einstein condensate loaded into a 1D moving optical lattice. The lifetime of the condensate in such a potential exhibits a dramatic dependence on the quasimomentum state. This is unambiguously attributed to the onset of dynamical instability, after a comparison with the predictions of the Gross-Pitaevskii theory. Deeply in the unstable region we observe the rapid appearance of complex structures in the atomic density profile, as a consequence of the condensate phase uniformity breakdown.
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Affiliation(s)
- L Fallani
- LENS, Dipartimento di Fisica, and INFM, Università di Firenze, via Nello Carrara 1, I-50019 Sesto Fiorentino (FI), Italy.
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42
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Pezzè L, Pitaevskii L, Smerzi A, Stringari S, Modugno G, de Mirandes E, Ferlaino F, Ott H, Roati G, Inguscio M. Insulating behavior of a trapped ideal Fermi gas. Phys Rev Lett 2004; 93:120401. [PMID: 15447234 DOI: 10.1103/physrevlett.93.120401] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2004] [Indexed: 05/24/2023]
Abstract
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 to an insulating regime as the Fermi energy moves from the first Bloch band into the band gap of the lattice. The conducting regime is characterized by an oscillation of the cloud about the potential minimum, while in the insulating case the center of mass remains on one side of the potential.
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Affiliation(s)
- L Pezzè
- Istituto Nazionale per la Fisica della Materia BEC-CRS and Dipartimento di Fisica, Università di Trento, I-38050 Povo, Italy
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43
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Ott H, de Mirandes E, Ferlaino F, Roati G, Türck V, Modugno G, Inguscio M. Radio frequency selective addressing of localized atoms in a periodic potential. Phys Rev Lett 2004; 93:120407. [PMID: 15447240 DOI: 10.1103/physrevlett.93.120407] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2004] [Indexed: 05/24/2023]
Abstract
We study the localization and addressability of ultracold atoms in a combined parabolic and periodic potential. Such a potential supports the existence of localized stationary states and we show that applying a radio frequency field allows us to selectively address atoms in these states. This method is used to measure the energy and momentum distribution of the atoms in the localized states. We also discuss possible extensions of this scheme to address and manipulate atoms in single lattice sites.
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Affiliation(s)
- H Ott
- LENS and Dipartimento di Fisica, Università di Firenze, Nello Carrara 1, 50019 Sesto Fiorentino, Italy
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44
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Roati G, de Mirandes E, Ferlaino F, Ott H, Modugno G, Inguscio M. Atom interferometry with trapped fermi gases. Phys Rev Lett 2004; 92:230402. [PMID: 15245144 DOI: 10.1103/physrevlett.92.230402] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2004] [Indexed: 05/24/2023]
Abstract
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 lattice results in macroscopic Bloch oscillations of the sample. The absence of interactions between fermions allows a time-resolved study of many periods of the oscillations, leading to a sensitive determination of the acceleration of gravity. The experiment proves the superiority of noninteracting fermions with respect to bosons for precision interferometry and offers a way for the measurement of forces with microscopic spatial resolution.
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Affiliation(s)
- G Roati
- LENS and Dipartimento di Fisica, University of Florence, and INFM, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
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45
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Ott H, de Mirandes E, Ferlaino F, Roati G, Modugno G, Inguscio M. Collisionally induced transport in periodic potentials. Phys Rev Lett 2004; 92:160601. [PMID: 15169210 DOI: 10.1103/physrevlett.92.160601] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2003] [Indexed: 05/24/2023]
Abstract
We study the transport of ultracold atoms in a tight optical lattice. For identical fermions the system is insulating under an external force while for bosonic atoms it is conducting. This reflects the different collisional properties of the particles and reveals the role of interparticle collisions in establishing a macroscopic transport in a perfectly periodic potential. Also in the case of fermions we can induce a transport by creating a collisional regime through the addition of bosons. We investigate the transport as a function of the collisional rate and observe a transition from a regime in which the mobility increases with increasing collisional rate to one in which it decreases. We compare our data with a theoretical model for electron transport in solids introduced by Esaki and Tsu.
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Affiliation(s)
- H Ott
- LENS and Dipartimento di Fisica, Università di Firenze, and INFM, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy.
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46
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Ferlaino F, De Mirandes E, Roati G, Modugno G, Inguscio M. Expansion of a Fermi gas interacting with a Bose-Einstein condensate. Phys Rev Lett 2004; 92:140405. [PMID: 15089523 DOI: 10.1103/physrevlett.92.140405] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2003] [Indexed: 05/24/2023]
Abstract
We study the expansion of an atomic Fermi gas interacting attractively with a Bose-Einstein condensate. We observe a slower evolution of the radial-to-axial aspect ratio which reveals the importance of the mutual attraction between the two samples during the first phase of the expansion. For large atom numbers, we also observe a bimodal momentum distribution of the Fermi gas, which reflects the spatial distribution of the mixture in trap. This effect allows us to extract important information on the overlap of the two species across the collapse.
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Affiliation(s)
- F Ferlaino
- LENS and Dipartimento di Fisica, Università di Firenze, and INFM, Via Nello Carrara 1, 50019 Sesto Fiorentino, Italy
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47
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Pastor PC, Giusfredi G, De Natale P, Hagel G, De Mauro C, Inguscio M. Absolute frequency measurements of the 2(3)S1-->2(3)P 0,1,2 atomic helium transitions around 1083 nm. Phys Rev Lett 2004; 92:023001. [PMID: 14753933 DOI: 10.1103/physrevlett.92.023001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2003] [Indexed: 05/24/2023]
Abstract
We measure the frequency of the 2(3)S1-->2(3)P(0,1,2) transitions of helium in a metastable beam using an optical frequency comb synthesizer. The relative uncertainty of these measurements ranging from 5x10(-11) to 7x10(-12) is, to our knowledge, the most precise result for any optical helium transition. Considering existing accurate values of the 2(3)P fine structure, we measure a centroid value of the 2(3)S-2(3)P frequency of 276 736 495 624.6(2.4) kHz, improving the previous interferometric measurement by 30 times. New accurate values of the 2(3)S-2(3)P and 2(3)P Lamb-shift energies are obtained.
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Affiliation(s)
- P Cancio Pastor
- Istituto Nazionale di Ottica Applicata (INOA), Largo E. Fermi 6, I-50125 Firenze, Italy
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48
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Fallani L, Cataliotti FS, Catani J, Fort C, Modugno M, Zawada M, Inguscio M. Optically induced lensing effect on a Bose-Einstein condensate expanding in a moving lattice. Phys Rev Lett 2003; 91:240405. [PMID: 14683097 DOI: 10.1103/physrevlett.91.240405] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2003] [Indexed: 05/24/2023]
Abstract
We report the experimental observation of a lensing effect on a Bose-Einstein condensate expanding in a moving 1D optical lattice. The effect of the periodic potential can be described by an effective mass dependent on the condensate quasimomentum. By changing the velocity of the atoms in the frame of the optical lattice, we induce a focusing of the condensate along the lattice direction. The experimental results are compared with the numerical predictions of an effective 1D theoretical model. In addition, a precise band spectroscopy of the system is carried out by looking at the real-space propagation of the atomic wave packet in the optical lattice.
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Affiliation(s)
- L Fallani
- European Laboratory for Non-Linear Spectroscopy (LENS), INFM and Dipartimento di Fisica, Università di Firenze, via Nello Carrara 1, I-50019 Sesto Fiorentino (FI), Italy.
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49
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Simoni A, Ferlaino F, Roati G, Modugno G, Inguscio M. Magnetic control of the interaction in ultracold K-Rb mixtures. Phys Rev Lett 2003; 90:163202. [PMID: 12731977 DOI: 10.1103/physrevlett.90.163202] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2003] [Indexed: 05/24/2023]
Abstract
We predict the presence of several magnetic Feshbach resonances in selected Zeeman sublevels of the isotopic pairs 40K-87Rb and 41K-87Rb at magnetic fields up to 10(3) G. Positions and widths are determined combining a new measurement of the 40K-87Rb inelastic cross section with recent experimental results on both isotopes. The possibility of driving a K-Rb mixture from the weak to the strong interacting regime tuning the applied field should allow one to achieve the optimal conditions for boson-induced Cooper pairing in a multicomponent 40K-87Rb atomic gas and for the production of ultracold polar molecules.
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Affiliation(s)
- A Simoni
- INFM and Department of Chemistry, University of Perugia, I-06123 Perugia, Italy
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50
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Fort C, Cataliotti FS, Fallani L, Ferlaino F, Maddaloni P, Inguscio M. Collective excitations of a trapped Bose-Einstein condensate in the presence of a 1D optical lattice. Phys Rev Lett 2003; 90:140405. [PMID: 12731902 DOI: 10.1103/physrevlett.90.140405] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2002] [Indexed: 05/24/2023]
Abstract
We study low-lying collective modes of an elongated 87Rb condensate produced in a 3D magnetic harmonic trap with the addition of a 1D periodic potential which is provided by a laser standing wave along the axial direction. While the transverse breathing mode remains unperturbed, quadrupole and dipole oscillations along the optical lattice are strongly modified. Precise measurements of the collective mode frequencies at different heights of the optical barriers provide a stringent test of the theoretical model recently introduced [M. Krämer, Phys. Rev. Lett. 88, 180404 (2002)]].
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Affiliation(s)
- C Fort
- LENS, Dipartimento di Fisica, Università di Firenze and Istituto Nazionale per la Fisica della Materia, via Nello Carrara 1, I-50019 Sesto Fiorentino (Florence), Italy
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