A5086303239- Cold Atom Physics and Bose-Einstein Condensates
- Quantum Information and Cryptography
- Quantum optics and atomic interactions
- Quantum Mechanics and Applications
- Mechanical and Optical Resonators
- Photonic and Optical Devices
- Atomic and Subatomic Physics Research
- Advanced Fiber Laser Technologies
- Strong Light-Matter Interactions
- Advanced Frequency and Time Standards
- Advanced MEMS and NEMS Technologies
- Optical Wireless Communication Technologies
- Quantum Computing Algorithms and Architecture
- Laser-Matter Interactions and Applications
- Spectroscopy and Laser Applications
- Quantum, superfluid, helium dynamics
- Advanced Thermodynamics and Statistical Mechanics
- Nonlinear Optical Materials Studies
- Optical Network Technologies
- Luminescence and Fluorescent Materials
- Plasmonic and Surface Plasmon Research
- Advanced Photonic Communication Systems
- Semiconductor Lasers and Optical Devices
- Orbital Angular Momentum in Optics
- Smart Parking Systems Research
University of Florence
2015-2025
European Theoretical Spectroscopy Facility
2001-2025
National Institute of Optics
2017-2024
National Research Council
2024
Institute for Complex Systems
2020
Istituto Nazionale di Ricerca Metrologica
2020
Quantum Science and Technology in Arcetri
2014-2019
Florence (Netherlands)
2019
Istituto Nazionale di Fisica Nucleare, Sezione di Firenze
2008-2015
Istituto Nazionale di Fisica Nucleare
1997-2013
We report on the direct observation of an oscillating atomic current in a one-dimensional array Josephson junctions realized with Bose-Einstein condensate. The is created by laser standing wave, condensates trapped valleys periodic potential and weakly coupled interwell barriers. coherence multiple tunneling between adjacent wells continuously probed interference. square small-amplitude oscillation frequency proportional to microscopic rate each condensate through barriers provides...
The Quantum Internet is envisioned as the final stage of quantum revolution, opening fundamentally new communications and computing capabilities, including distributed computing. But governed by laws mechanics. Phenomena with no counterpart in classical networks, such no-cloning, measurement, entanglement teleporting, impose very challenging constraints for network design. Specifically, functionalities, ranging from error-control mechanisms to overhead-control strategies, are based on...
We create Bose-Einstein condensates of 87Rb in a static magnetic trap with superimposed blue-detuned 1D optical lattice. By displacing the center we are able to control condensate evolution. observe change frequency center-of-mass oscillation harmonic trapping potential, analogy an increase effective mass. For fluid velocities greater than local speed sound, onset dissipative processes up full removal superfluid component. A parallel simulation study visualizes dynamics and accounts for main...
In the present work we demonstrate how to realize a 1D closed optical lattice experimentally, including tunable boundary phase twist. The latter may induce "persistent currents" visible by studying atoms' momentum distribution. We show important phenomena in physics can be studied physical realization of systems trapped atoms ring-shaped lattices. A mixture bosonic and/or fermionic loaded into lattice, realizing generic quantum system many interacting particles.
We present here an all-optical scheme for the experimental realization of a quantum phase gate. It is based on polarization degree freedom two traveling single-photon wave packets and exploits giant Kerr nonlinearities that can be attained in coherently driven ultracold atomic media.
We report the experimental observation of disruption superfluid atomic current flowing through an array weakly linked Bose–Einstein condensates. The condensates are trapped in optical lattice superimposed on a harmonic magnetic potential. dynamical response system to change potential minimum along axis goes from coherent oscillation (superfluid regime) localization trap ('classical' insulator regime). occurs when initial displacement is larger than critical value or, equivalently, velocity...
It is generally impossible to probe a quantum system without disturbing it. However, it possible exploit the back action of measurements and strong couplings tailor protect coherent evolution system. This profound counterintuitive phenomenon known as Zeno dynamics. Here we demonstrate dynamics with rubidium Bose-Einstein condensate in five-level Hilbert space. We harness dynamically disconnect different groups states constrain atoms coherently evolve inside two-level subregion. In parallel...
Around forty years have passed since the first pioneering works introduced possibility of using quantum physics to strongly enhance communications safety. Nowadays Quantum Cryptography, and in particular, Key Distribution (QKD) exited laboratories become commercial technologies that increasingly trigger attention States, military forces, banks, private corporations. This work takes on challenge bringing QKD closer a consumer technology: optical fibers deployed used by telecommunication...
We investigate the properties of a coherent array containing about 200 Bose-Einstein condensates produced in far detuned 1D optical lattice. The density profile gas, imaged after releasing trap, provides information coherence ground-state wavefunction. measured atomic distribution is characterized by interference peaks. time evolution peaks, their relative population as well radial size expanding cloud are good agreement with predictions theory. 2D nature trapped and conditions required to...
We analyze the nonlinear optical response of a four-level atomic system driven into tripod configuration. The large cross-Kerr nonlinearities that occurr in such are shown to produce phase shift order $\pi$. Such substantial may be observed cold gas magneto-optical trap where it coupl fasibly exploited towards realization polarization quantum gate. experimental feasibility gate is here examined detail.
Quantum technologies could largely benefit from the control of quantum emitters in sub-micrometric size crystals. These are naturally prone to integration hybrid devices, including heterostructures and complex photonic devices. Currently available nanocrystals suffer spectral instability, preventing their use as single-photon sources for most optics operations. In this work we report on performances emission organic (average hundreds nm), made anthracene (Ac) doped with dibenzoterrylene...
The integration of Visible-Light Communications technology (VLC) in Intelligent Transportation Systems (ITS) is a very promising platform for cost-effective implementation revolutionary ITS and cooperative protocols. In this paper, we propose an infrastructure-to-vehicle-to-vehicle (I2V2V) VLC system ITS, implementing it through regular LED traffic light serving as transmitter digital Active Decode-and-Relay (ADR) stage decoding relaying the received information towards further incoming...
Quantum key distribution (QKD) allows the of cryptographic keys between multiple users in an information-theoretic secure way, exploiting quantum physics. While current QKD systems are mainly based on attenuated laser pulses, deterministic single-photon sources could give concrete advantages terms secret rate (SKR) and security owing to negligible probability multi-photon events. Here, we introduce demonstrate a proof-of-concept system molecule-based source operating at room temperature...
We study the phase transition of a gas Rb atoms to quantum degeneracy in combined potential harmonically confining magnetic trap and periodic an optical lattice. For high lattice potentials we observe significant change temperature dependency population ground state system. The experimental results are explained by subsequent formation quasi 2D condensates single sites.
The on-chip integration of quantum light sources and nonlinear elements constitutes a major step toward scalable photon-based information processing communication. In this work we demonstrate the potential hybrid technology that combines organic-molecule-based emitters dielectric chips consisting ridge waveguides grating far-field couplers. particular, dibenzoterrylene molecules in thin anthracene crystals are used as single-photon sources, exhibiting long-term photostability, easy...
We report the confinement of an optomechanical micro-oscillator in a squeezed thermal state, obtained by parametric modulation optical spring. propose and implement experimental scheme based on feedback control oscillator, which stabilizes amplified quadrature while leaving orthogonal one unaffected. This technique allows us to surpass -3dB limit noise reduction, associated resonance, with best result -7.4dB. In moderately cooled system, our can be efficiently exploited produce strong...
The efficient interaction of light with quantum emitters is crucial to most applications in nano and photonics, such as sensing or information processing. Effective excitation photon extraction are particularly important for the weak signals emitted by a single atom molecule. Recent works have introduced novel collection strategies, which demonstrate that large efficiencies can be achieved either planar dielectric antennas combined high numerical aperture objectives optical nanostructures...
Abstract In-field demonstrations in real-world scenarios boost the development of a rising technology towards its integration existing infrastructures. Although quantum key distribution (QKD) devices are already adopted outside laboratories, current field implementations still suffer from high costs and low performances, preventing this emerging large-scale deployment telecommunication networks. Here we present simple, practical efficient QKD scheme with finite-key analysis, performed over...
The authors analyze the energy transfer in a quantum system by experimentally accessing exchange statistics of subjected to stochastic projective measurements. Employing nitrogen-vacancy spin diamond interacting with tunable dissipation channel, they demonstrate validity fluctuation relation for an open system.
Engineered dynamical maps combining coherent and dissipative transformations of quantum states with measurements, have demonstrated a number technological applications, promise to be crucial tool in thermodynamic processes. Here, we exploit the control on effective open spin qutrit dynamics an NV center, experimentally realize autonomous feedback process (Maxwell demon) tunable strength. The is enabled by random measurement events that condition subsequent evolution qutrit. efficacy Maxwell...
We present the results of an experiment on light scattering from elongated Bose-Einstein condensate (BEC) interacting with a far-off-resonant pump laser. By collective atomic recoil lasing (CARL) coherent superposition two wave packets different momenta is created. Varying intensity weak counterpropagating laser beam we observe transition pure superradiant regime to Bragg regime, where Rabi oscillations in two-level system are observed. The process limited by decoherence between packets. In...
We report the experimental observation of a lensing effect on Bose-Einstein condensate expanding in moving 1D optical lattice. The periodic potential can be described by an effective mass dependent quasimomentum. By changing velocity atoms frame lattice, we induce focusing along lattice direction. results are compared with numerical predictions theoretical model. In addition, precise band spectroscopy system is carried out looking at real-space propagation atomic wave packet
We report on the microscopic imaging of individual sites an optical lattice with a period 5.3 \ensuremath{\mu}m created by retroreflected, focused ${\mathrm{CO}}_{2}$-laser beam. In this one-dimensional lattice, Lamb-Dicke limit is fulfilled in all three spatial dimensions. Single have been individually addressed near-resonant laser Because negligible decoherence rate from spontaneous photon scattering such holds intriguing prospects for realization fault-tolerant quantum logic gates.