0000000000543257

AUTHOR

Th. Best

showing 3 related works from this author

Free fermion antibunching in a degenerate atomic Fermi gas released from an optical lattice

2006

Noise in a quantum system is fundamentally governed by the statistics and the many-body state of the underlying particles. Whereas for bosonic particles the correlated noise observed for e.g. photons or bosonic neutral atoms can still be explained within a classical field description with fluctuating phases, the anticorrelations in the detection of fermionic particles have no classical analogue. The observation of such fermionic antibunching is so far scarce and has been confined to electrons and neutrons. Here we report on the first direct observation of antibunching of neutral fermionic atoms. Through an analysis of the atomic shot noise in a set of standard absorption images, of a gas of…

PhysicsCondensed Matter::Quantum GasesQuantum PhysicsOptical latticeMultidisciplinaryDegenerate energy levelsFOS: Physical sciencesQuantum phasesFermionCondensed Matter - Soft Condensed MatterFermionic condensateCondensed Matter - Other Condensed MatterQuantum mechanicsQuantum systemSoft Condensed Matter (cond-mat.soft)Fermi gasQuantum Physics (quant-ph)QuantumOther Condensed Matter (cond-mat.other)
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Coherent and incoherent spectral broadening in a photonic crystal fiber.

2007

The coherence of the spectral broadening process is the key requisite for the application of supercontinua in frequency combs. We investigate the coherence of two subsequent supercontinuum pulses created in a photonic crystal fiber pumped by a femtosecond laser. We measure Young interference fringes from a Michelson-type interferometer at different wavelengths of the output spectrum and analyze their dependence on pump intensity and polarization. The visibility of these fringes is a direct measure of the coherence of the spectral broadening processes.

PhysicsOptical fiberbusiness.industryPhysics::OpticsLaserAtomic and Molecular Physics and Opticslaw.inventionSupercontinuumCoherence lengthInterferometryOpticslawOptoelectronicsbusinessPhotonic-crystal fiberDoppler broadeningPhotonic crystalOptics letters
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Metallic and Insulating Phases of Repulsively Interacting Fermions in a 3D Optical Lattice

2008

The fermionic Hubbard model plays a fundamental role in the description of strongly correlated materials. Here we report on the realization of this Hamiltonian using a repulsively interacting spin mixture of ultracold $^{40}$K atoms in a 3D optical lattice. We have implemented a new method to directly measure the compressibility of the quantum gas in the trap using in-situ imaging and independent control of external confinement and lattice depth. Together with a comparison to ab-initio Dynamical Mean Field Theory calculations, we show how the system evolves for increasing confinement from a compressible dilute metal over a strongly-interacting Fermi liquid into a band insulating state. For …

PhysicsCondensed Matter::Quantum GasesOptical latticeMultidisciplinaryStrongly Correlated Electrons (cond-mat.str-el)Hubbard modelCondensed matter physicsFOS: Physical sciencesFermionsymbols.namesakeCondensed Matter - Strongly Correlated ElectronsMean field theorysymbolsStrongly correlated materialCondensed Matter::Strongly Correlated ElectronsFermi liquid theoryMetal–insulator transitionHamiltonian (quantum mechanics)
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