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Related papers: The HMF model for fermions and bosons

200 papers

We propose a relationship between thermodynamic phase transitions and ground-state quantum phase transitions in systems with variable Hamiltonian parameters. It is based on a link between zeros of the canonical partition function at complex…

Nuclear Theory · Physics 2009-11-10 Pavel Cejnar , Stefan Heinze , Jan Dobes

The Hamiltonian Mean-Field (HMF) model belongs to a broad class of statistical physics models with non-additive Hamiltonians that reveal many non-trivial properties, such as non-equivalence of statistical ensembles, ergodicity breaking, and…

Statistical Mechanics · Physics 2019-11-25 Piotr Fronczak , Agata Fronczak , Anna Chmiel , Julian Sienkiewicz

The phase transitions at finite temperatures in the systems described by the Bose-Fermi-Hubbard model are investigated in this work in the framework of the selfconsistent random phase approximation. The case of the hard-core bosons is…

Other Condensed Matter · Physics 2010-09-07 T S Mysakovych

We consider a one-dimensional optical lattice of three-dimensional Harmonic Oscillators which are loaded with neutral fermionic atoms trapped into two hyperfine states. By means of a standard variational coherent-state procedure, we derive…

Other Condensed Matter · Physics 2009-11-11 F. P. Massel , V. Penna

A spin version of dynamical mean-field theory is extended for magnetically ordered states in the Heisenberg model. The self-consistency equations are solved with high numerical accuracy by means of the continuous-time quantum Monte Carlo…

Strongly Correlated Electrons · Physics 2013-08-02 Junya Otsuki , Yoshio Kuramoto

We analyze the quantum phase transition between a semimetal and a superfluid in a model of attractively interacting fermions with a linear dispersion. The quantum critical properties of this model cannot be treated by the Hertz-Millis…

Strongly Correlated Electrons · Physics 2011-06-06 P. Strack , S. Takei , W. Metzner

We use a semiclassical three-fluid thermodynamic model to evaluate the phenomena of spatial demixing in mesoscopic clouds of fermionic and bosonic atoms at high dilution under harmonic confinement, assuming repulsive boson-boson and…

Statistical Mechanics · Physics 2009-11-07 Z. Akdeniz , A. Minguzzi , P. Vignolo , M. P. Tosi

A two component model of negative U centers coupled with the Fermi sea of itinerant fermions is discussed in connection with high-temperature superconductivity of cuprates, and superfluidity of atomic fermions. We examine the phase…

Superconductivity · Physics 2009-11-10 A. S. Alexandrov

In this brief report, following the recent developments on formulating a quantum analogue of the classical energy equipartition theorem for open systems where the heat bath comprises of independent oscillators, i.e. bosonic degrees of…

Statistical Mechanics · Physics 2022-06-14 Jasleen Kaur , Aritra Ghosh , Malay Bandyopadhyay

The influence of boson-boson and boson-fermion interactions on the stability of a binary mixture of bosonic and fermionic atoms is investigated. The density profiles of the trapped mixture are obtained from direct numerical solution of a…

Statistical Mechanics · Physics 2009-11-07 R. Roth , H. Feldmeier

A recent time-of-flight (TOF) expansion experiment with polarized fermionic erbium atoms measured a Fermi surface deformation from a sphere to an ellipsoid due to dipole-dipole interaction, thus confirming previous theoretical predictions.…

Quantum Gases · Physics 2017-05-30 Vladimir Veljic , Antun Balaz , Axel Pelster

We analyze the many-particle Schrodinger equation for fermions in a thermal ensemble by introducing an exponential operator expansion, defined in the context of thermofield dynamics. The expansion is optimized variationally at each time…

Statistical Mechanics · Physics 2020-01-10 Edward B. Baker

A novel approach for studying phase transitions in systems with quantum degrees of freedom is discussed. Starting from the microscopic hamiltonian of a quantum model, we first derive a set of exact differential equations for the free energy…

Strongly Correlated Electrons · Physics 2009-10-31 Pietro Gianinetti , Alberto Parola

We present a detailed Hamiltonian treatment of an inhomogeneous fermionic perturbation propagating on a closed FLRW spacetime quantized via LQC. Expanding the fermion in spinor harmonics on spatial 3-sphere and truncating at quadratic…

General Relativity and Quantum Cosmology · Physics 2025-10-02 Yaser Tavakoli , Ahad K. Ardabili , Sara Mosaddegh

We study the nonequilibrium steady-state of a fully-coupled network of $N$ quantum harmonic oscillators, interacting with two thermal reservoirs. Given the long-range nature of the couplings, we consider two setups: one in which the number…

Statistical Mechanics · Physics 2022-09-27 Francesco Andreucci , Stefano Lepri , Stefano Ruffo , Andrea Trombettoni

We describe a one-dimensional self-gravitating system derived from the problem of large-scale structure formation in cosmology. Considering small times so that the expansion can be neglected we present a thermodynamical analysis of this…

Astrophysics · Physics 2009-11-11 Patrick Valageas

Violent relaxation is a process that occurs in systems with long-range interactions. It has the peculiar feature of dramatically amplifying small perturbations, and rather than driving the system to equilibrium it instead leads to slowly…

Statistical Mechanics · Physics 2018-07-18 Ryan Plestid , Perry Mahon , Duncan O'Dell

We consider the quantum many-body evolution of a homogeneous Fermi gas in three dimensions in the coupled semiclassical and mean-field scaling regime. We study a class of initial data describing collective particle-hole pair excitations on…

Mathematical Physics · Physics 2022-07-07 Niels Benedikter , Phan Thành Nam , Marcello Porta , Benjamin Schlein , Robert Seiringer

An analytical solution for the out-of-equilibrium quasi-stationary states of the paradigmatic Hamiltonian Mean Field (HMF) model can be obtained from a maximum entropy principle. The theory has been so far tested with reference to a…

Statistical Mechanics · Physics 2012-04-17 Mallbor Assllani , Duccio Fanelli , Alessio Turchi , Timoteo Carletti , Xavier Leoncini

Beginning from the semiclassical Hamiltonian, the Fermi pressure and Bohm potential for the quantum hydrodynamics application (QHD) at finite temperature are consistently derived in the framework of the local density approximation with the…

Plasma Physics · Physics 2018-04-18 Zh. A. Moldabekov , M. Bonitz , T. S. Ramazanov