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Related papers: Spin 1/2 Fermions in the Unitary Limit

200 papers

Recently we have computed the third order corrections to the ground state energy of the arbitrarily polarized diluted gas of spin 1/2 fermions interacting through a spin-independent repulsive two-body potential. Here we extend this result…

Quantum Gases · Physics 2023-07-05 Piotr H. Chankowski , Jacek Wojtkiewicz , Szymon Augustynowicz

We derive an energy density functional for non-relativistic spin one-half fermions in the limit of a divergent two-body scattering length. Using an epsilon expansion around d=4-epsilon spatial dimensions we compute the coefficient of the…

Nuclear Theory · Physics 2009-03-24 Gautam Rupak , Thomas Schaefer

We experimentally determined various thermodynamic quantities of interacting two-component fermions at the zero-temperature limit from the Bardeen-Cooper-Schrieffer (BCS) region to the unitarity limit. The obtained results are very accurate…

The energy of the two-component Fermi gas with the s-wave contact interaction is a simple linear functional of its momentum distribution: $$E_\text{internal}=\hbar^2\Omega C/4\pi am+\sum_{\vect k\sigma}(\hbar^2 k^2/2m)(n_{\vect…

Statistical Mechanics · Physics 2015-06-25 Shina Tan

We report a measurement of the condensation energy of a two-component Fermi gas with tunable interactions. From the equation of state of the gas, we infer the properties of the normal phase in the zero-temperature limit. By comparing the…

We study spin-1/2 fermions in spin dependent potentials under the \emph{spin model approximation}, in which interatomic collisions that change the total occupation of single-particle modes are ignored. The spin model approximation maps the…

Quantum Gases · Physics 2020-09-02 Michael L. Wall

We consider two-component fermions on the lattice in the unitarity limit. This is an idealized limit of attractive fermions where the range of the interaction is zero and the scattering length is infinite. Using Euclidean time projection,…

Nuclear Theory · Physics 2008-11-26 Dean Lee

Ground state energies and superfluid gaps are calculated for degenerate Fermi systems interacting via long attractive scattering lengths such as cold atomic gases, neutron and nuclear matter. In the intermediate region of densities, where…

Condensed Matter · Physics 2009-10-31 H. Heiselberg

We consider an imbalanced mixture of two different ultracold Fermi gases, which are strongly interacting. Calling spin-down the minority component and spin-up the majority component, the limit of small relative density $x=n\ds /n\us$ is…

Quantum Gases · Physics 2012-01-05 S. Giraud , R. Combescot

We perform lattice Monte Carlo simulations for up to 66 unitary fermions in a finite box using a highly improved lattice action for nonrelativistic spin 1/2 fermions. We obtain a value of $0.366^{+0.016}_{-0.011}$ for the Bertsch parameter,…

High Energy Physics - Lattice · Physics 2015-06-04 Michael G. Endres , David B. Kaplan , Jong-Wan Lee , Amy N. Nicholson

The unitary Fermi gas is a many-body system of two-component fermions with zero-range interactions tuned to infinite scattering length. Despite much activity and interest in unitary Fermi gases and its universal properties, there have been…

Quantum Gases · Physics 2020-07-02 Rongzheng He , Ning Li , Bing-Nan Lu , Dean Lee

Semiclassical expansion of the Wigner function for spin-1/2 fermions having an effective spacetime-dependent mass is used to analyze spin-polarization effects. The existing framework is reformulated to obtain a differential equation…

High Energy Physics - Phenomenology · Physics 2024-01-24 Samapan Bhadury , Arpan Das , Wojciech Florkowski , Gowthama K. K. , Radoslaw Ryblewski

The momentum density, $n(k)$ of interacting many-body Fermionic systems is studied (for $k>k_F)$ using examples of several well-known two-body interaction models. This work shows that $n(k)$ can not be approximated by a zero-range model for…

Nuclear Theory · Physics 2018-02-14 Gerald A. Miller

Collisions of two fermionic dimers near the unitary limit are studied using exact four-particle equations for transition operators in momentum space. Universal properties of dimer-dimer phase shifts and effective range expansion (ERE)…

Quantum Gases · Physics 2017-08-09 A. Deltuva

Quantum gravity phenomenology opens up the possibility of probing Planck scale physics. Thus, by exploiting the generic properties that a semiclassical state of the compound system fermions plus gravity should have, an effective dynamics of…

High Energy Physics - Theory · Physics 2009-11-07 J. Alfaro , H. A. Morales-Tecotl , L. F. Urrutia

We study systems of few two-component fermions interacting in a Harmonic Oscillator trap. The fermion-fermion interaction is generated in a finite basis with a unitary transformation of the exact two-body spectrum given by the Busch…

Quantum Gases · Physics 2013-05-23 J. Rotureau

The energy-spectrum of two point-like particles interacting in a 3-D isotropic Harmonic Oscillator (H.O.) trap is related to the free scattering phase-shifts $\delta$ of the particles by a formula first published by Busch et al. It is here…

Nuclear Theory · Physics 2016-01-20 H. S. Köhler

The behavior of ultracold atomic gases depends crucially on the two-body scattering properties of these systems. We develop a multichannel scattering theory for atom-atom collisions in quasi-one-dimensional (quasi-1D) geometries such as…

Condensed Matter · Physics 2009-11-10 Brian E. Granger , D. Blume

We report quantum Monte Carlo calculations of superfluid Fermi gases with short-range two-body attractive interactions with infinite scattering length. The energy of such gases is estimated to be $(0.44 \pm 0.01)$ times that of the…

Atomic Physics · Physics 2009-11-10 J. Carlson , S. Y. Chang , V. R. Pandharipande , K. E. Schmidt

The unitarity limit describes interacting particles where the range of the interaction is zero and the scattering length is infinite. We present precision benchmark calculations for two-component fermions at unitarity using three different…

Quantum Gases · Physics 2011-06-27 Shahin Bour , Xin Li , Dean Lee , Ulf-G. Meißner , Lubos Mitas