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Related papers: Ground-state fidelity in the BCS-BEC crossover

200 papers

We investigate the quantum and thermal phase diagram of fermionic polar molecules loaded in a bilayer trapping potential with perpendicular dipole moment. We use both a BCS theory approach that is most realiable at weak-coupling and a…

Quantum Gases · Physics 2012-01-13 N. T. Zinner , B. Wunsch , D. Pekker , D. -W. Wang

We compute ground state fidelity of the one-dimensional Bose-Hubbard model at unit filling factor. To this aim, we apply the DMRG algorithm to systems with open and periodic boundary conditions. We find that fidelity differs significantly…

Strongly Correlated Electrons · Physics 2014-03-26 Mateusz Łacki , Bogdan Damski , Jakub Zakrzewski

We report on precision measurements of the frequency of the radial compression mode in a strongly interacting, optically trapped Fermi gas of Li-6 atoms. Our results allow for a test of theoretical predictions for the equation of state in…

Other Condensed Matter · Physics 2009-03-24 A. Altmeyer , S. Riedl , C. Kohstall , M. Wright , R. Geursen , M. Bartenstein , C. Chin , J. Hecker Denschlag , R. Grimm

We introduce a partial state fidelity approach to quantum phase transitions. We consider a superconducting lattice with a magnetic impurity inserted at its centre, and look at the fidelity between partial (either one-site or two-site)…

Quantum Physics · Physics 2009-11-13 N. Paunkovic , P. D. Sacramento , P. Nogueira , V. R. Vieira , V. K. Dugaev

We discuss an integrable model of interacting Fermions in one dimension, that allows an exact description of the crossover from a BCS- to a Bose-like superfluid. This model bridges the Gaudin-Yang model of attractive spin 1/2 Fermions to…

Statistical Mechanics · Physics 2007-05-23 J. N. Fuchs , A. Recati , W. Zwerger

We report the experimental measurement of the equation of state of a two-dimensional Fermi gas with attractive s-wave interactions throughout the crossover from a weakly coupled Fermi gas to a Bose gas of tightly bound dimers as the…

Quantum Gases · Physics 2016-02-02 I. Boettcher , L. Bayha , D. Kedar , P. A. Murthy , M. Neidig , M. G. Ries , A. N. Wenz , G. Zürn , S. Jochim , T. Enss

The crossover from weak coupling Bardeen-Cooper-Schrieffer (BCS) pairing to a Bose-Einstein condensate (BEC) of tightly bound pairs, as a function of the attractive interaction in Fermi systems, has long been of interest to theoretical…

Quantum Gases · Physics 2014-04-09 Mohit Randeria , Edward Taylor

We investigate the crossover from BCS pairing to molecular BEC in an atomic gas with two fermion species with masses $m_\up \ne m_\dn$ tuned through a Feshbach resonance. We present results for the T=0 equation of state as a function of the…

Quantum Gases · Physics 2015-05-13 Roberto B. Diener , Mohit Randeria

We investigate the phase diagram of two-component fermions in the BCS-BEC crossover. Using functional renormalization group equations we calculate the effect of quantum fluctuations on the fermionic self-energy parametrized by a…

Quantum Gases · Physics 2010-11-12 S. Floerchinger , M. M. Scherer , C. Wetterich

Motivated by recent development in quantum fidelity and fidelity susceptibility, we study relations among Lie algebra, fidelity susceptibility and quantum phase transition for a two-state system and the Lipkin-Meshkov-Glick model. We get…

Quantum Physics · Physics 2011-04-11 Li-Jun Tian , Chang-Qing Zhu , Hong-Biao Zhang , Li-Guo Qin

We develop a self-consistent theory unifying the description of a quantum Fermi gas in the presence of a Fano-Feshbach resonance in the whole phase diagram ranging from BCS to BEC type of superfluidity and from narrow to broad resonances,…

Quantum Gases · Physics 2019-08-29 Pietro Maria Bonetti , Maria Luisa Chiofalo

This paper gives a survey of a diagrammatic approach for fermionic pairing fluctuations, which are relevant to the BCS-BEC crossover realized with ultracold Fermi gases. Emphasis will be given to the physical intuition about the relevant…

Quantum Gases · Physics 2010-11-29 G. C. Strinati

We study the BCS-BEC crossover in the strongly correlated regime of an ultra-cold rotating two component Fermi gas. Strong correlations are shown to generate an additional long-range interaction which results in a modified crossover region…

Mesoscale and Nanoscale Physics · Physics 2007-10-30 S. G. Bhongale , M. R. Goosen , S. J. J. M. F. Kokkelmans

We consider the BCS-BEC crossover for a system of trapped Fermi atoms at finite temperature, both below and above the superfluid critical temperature, by including fluctuations beyond mean field. We determine the superfluid critical…

Superconductivity · Physics 2009-02-20 A. Perali , P. Pieri , L. Pisani , G. C. Strinati

Theoretical treatments of the BCS-BEC crossover need to provide as accurate as possible descriptions of the two regimes where the diluteness condition applies, either in terms of the constituent fermions (BCS limit) or of the composite…

Superconductivity · Physics 2007-05-23 P. Pieri , G. C. Strinati

We investigate the non-universal behavior of the BCS-BEC crossover model at the normal to superfluid transition. By using a finite temperature quantum field theoretical approach due to Nozieres and Schmitt-Rink and by making the effective…

Superconductivity · Physics 2007-05-23 L. M. Jensen

We examine distinct measures of fermionic entanglement in the exact ground state of a finite superconducting system. It is first shown that global measures such as the one-body entanglement entropy, which represents the minimum relative…

Quantum Physics · Physics 2018-06-20 M. Di Tullio , N. Gigena , R. Rossignoli

Recently it has been shown that the fidelity of the ground state of a quantum many-body system can be used to detect its quantum critical points (QCPs). If g denotes the parameter in the Hamiltonian with respect to which the fidelity is…

Statistical Mechanics · Physics 2015-06-11 Manisha Thakurathi , Diptiman Sen , Amit Dutta

An efficient algorithm is developed for quantum spin tubes in the context of the tensor network representations. It allows to efficiently compute the ground-state fidelity per lattice site, which in turn enables us to identify quantum…

Statistical Mechanics · Physics 2011-05-17 Ai-Min Chen , Qian-Qian Shi , Jin-Hua Liu , Huan-Qiang Zhou

We study Gaussian fluctuations of the zero-temperature attractive Fermi gas in the 2D BCS-BEC crossover showing that they are crucial to get a reliable equation of state in the BEC regime of composite bosons, bound states of fermionic…

Quantum Gases · Physics 2015-01-27 L. Salasnich , F. Toigo