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Related papers: Finite-range effects in the unitary Fermi polaron

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The ultra-cold and weakly-coupled Fermi gas in two spatial dimensions is studied in an effective field theory framework. It has long been observed that universal corrections to the energy density to two orders in the interaction strength do…

Quantum Gases · Physics 2023-04-26 Silas R. Beane , Gianluca Bertaina , Roland C. Farrell , William R. Marshall

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…

We calculate the one-body temperature Green's (Matsubara) function of the unitary Fermi gas via Quantum Monte Carlo, and extract the spectral weight function $A(p,\omega)$ using the methods of maximum entropy and singular value…

Statistical Mechanics · Physics 2009-11-22 P. Magierski , G. Wlazlowski , A. Bulgac , J. E. Drut

We present calculations for spin $ 1/2 $ fermions at unitarity limit, where the effective range of the interaction is zero and the scattering length is infinite. We compute the ground-state energy for a system of 6, 10,14,18 and 20…

Strongly Correlated Electrons · Physics 2017-10-18 Faisal Etminan , Mohammad Mehdi Firoozabadi

Quantum Monte Carlo calculations of the relaxation energy, pair-correlation function, and annihilating-pair momentum density are presented for a positron immersed in a homogeneous electron gas. We find smaller relaxation energies and…

Statistical Mechanics · Physics 2011-11-09 N. D. Drummond , P. Lopez Rios , C. J. Pickard , R. J. Needs

We apply a diagrammatic Monte Carlo method to the problem of an impurity interacting resonantly with a homogeneous Fermi bath for a quasi-two-dimensional setup. Notwithstanding the series divergence, we can show numerically that the three…

Quantum Gases · Physics 2014-09-18 Peter Kroiss , Lode Pollet

An efficient continuous-time path-integral Quantum Monte Carlo algorithm for the lattice polaron is presented. It is based on Feynman's integration of phonons and subsequent simulation of the resulting single-particle self-interacting…

Strongly Correlated Electrons · Physics 2009-10-31 P E Kornilovitch

An impurity atom immersed in an ultracold atomic Fermi gas can form a quasiparticle, so-called Fermi polaron, due to impurity-fermion interaction. We consider a three-dimensional homogeneous dipolar Fermi gas as a medium, where the…

The study of polaron of an open quantum system plays an important role in both verifying the effectiveness of approximate many-body theory and predicting novel quantum phenomenone in open quantum systems. In a pioneering work, Piazza et al…

Quantum Gases · Physics 2022-06-22 Ye Cao , Jing Zhou

We investigate the properties of an impurity immersed in an ensemble of spin-polarized fermions confined in a tight quantum wire. We use a non-perturbative variational approach that accounts for virtual transverse excitations and…

Quantum Gases · Physics 2025-09-08 Lovro Anto Barišić , Giuliano Orso , Frédéric Chevy , Kris Van Houcke

We calculate the equation of state of a two-component Fermi gas with attractive short-range interspecies interactions using the fixed-node diffusion Monte Carlo method. The interaction strength is varied over a wide range by tuning the…

Soft Condensed Matter · Physics 2009-11-10 G. E. Astrakharchik , J. Boronat , J. Casulleras , S. Giorgini

We investigate the 1D interacting two-component Fermi gas with arbitrary polarization. Exact results for the ground state energy, quasimomentum distribution functions, spin velocity and charge velocity reveal subtle polarization dependent…

Strongly Correlated Electrons · Physics 2007-05-23 M. T. Batchelor , M. Bortz , X. W. Guan , N. Oelkers

Ultracold Fermi gases with tuneable interactions represent a unique test bed to explore the many-body physics of strongly interacting quantum systems. In the past decade, experiments have investigated a wealth of intriguing phenomena, and…

We provide an analytically tractable toy model of an infinitely heavy impurity interacting with the spin-polarized gas of bath fermions via a contact potential in 1D and placed in a harmonic trap. The solution to this problem requires…

Quantum Gases · Physics 2025-09-03 Nikolay Yegovtsev

Two-dimensional spin-1/2 fermions with the finite-range interaction are theoretically studied. Characterizing the attractive interaction in terms of the scattering length and the effective range, we discuss the finite-range effects on the…

Quantum Gases · Physics 2023-05-31 Hikaru Sakakibara , Hiroyuki Tajima , Haozhao Liang

A density functional theory is proposed for strongly interacting fermions with arbitrary large negative scattering length. The functional has only two parameters that are directly fixed to reproduce the universal properties of unitary gas:…

Nuclear Theory · Physics 2016-11-03 Denis Lacroix

A one dimensional Fermi mixture with delta--interaction is investigated in the limit of extreme imbalance. In particular we consider the cases of only one or two minority Fermions which interact with the Fermi-sea of the majority Fermions.…

Quantum Gases · Physics 2013-06-28 Christian Recher , Heinerich Kohler

We present Quantum Monte Carlo calculations of the properties of a two-component mass imbalanced Fermi gas, corresponding to the $^6$Li-$^{40}$K mixture. We compute the equation of state of the unpolarized system as a function of the…

Quantum Gases · Physics 2024-10-29 Stefano Gandolfi , Ryan Curry , Alexandros Gezerlis

A Fermi gas of cold atoms allows precise control over the dimensionless effective range, $k_\mathrm{F} R_\mathrm{eff}$, of the Feshbach resonance. Our pseudopotential formalism allows us to create smooth potentials with effective range, $-2…

Quantum Gases · Physics 2017-02-07 L. M. Schonenberg , G. J. Conduit

Highly polarized mixtures of atomic Fermi gases constitute a novel Fermi liquid. We demonstrate how information on thermodynamic properties may be used to calculate quasiparticle scattering amplitudes even when the interaction is resonant…

Statistical Mechanics · Physics 2008-06-19 G. M. Bruun , A. Recati , C. J. Pethick , H. Smith , S. Stringari