Results 11 to 20 of about 1,422 (47)

Virial expansion with Feynman diagrams

, 2011
We present a field theoretic method for the calculation of the second and third virial coefficients b2 and b3 of 2-species fermions interacting via a contact interaction. The method is mostly analytic. We find a closed expression for b3 in terms of the 2
A. A. Abrikosov, A. A. Vedenov, G. V. Skorniakov, G. V. Skorniakov, I. S. Gradshteyn, L. D. Landau, X. Leyronas   +6 more
core   +1 more source

On interacting fermions and bosons with definite total momentum [PDF]

, 2004
Any {\it exact} eigenstate with a definite momentum of a many-body Hamiltonian can be written as an integral over a {\it symmetry-broken} function $\Phi$.
A. L. Fetter, Alexej I. Streltsov, J.-P. Blaizot, Lorenz S. Cederbaum, Ofir E. Alon   +4 more
core   +2 more sources

Strong coupling treatment of the polaronic system consisting of an impurity in a condensate

, 2010
The strong coupling treatment of the Fr\"ohlich-type polaronic system, based on a canonical transformation and a standard Landau-Pekar type variational wave function, is applied to the polaronic system consisting of an impurity in a condensate.
Casteels, W., Devreese, J. T., Tempere, J., Van Cauteren, T.   +3 more
core   +1 more source

Relation between the thermodynamic Casimir effect in Bose-gas slabs and critical Casimir forces

, 2006
In a recent letter, Martin and Zagrebnov [Europhys. Lett., 73 (2006) 1] discussed the thermodynamic Casimir effect for the ideal Bose gas confined in a thin film.
Dietrich, S., Gambassi, A.
core   +1 more source

Path-integral Monte Carlo and the squeezed trapped Bose-Einstein gas

, 2006
Bose-Einstein condensation has been experimentally found to take place in finite trapped systems when one of the confining frequencies is increased until the gas becomes effectively two-dimensional (2D).
Fernández, Juan Pablo, Mullin, William J.   +1 more
core   +1 more source

Weakly-Interacting Bosons in a Trap within Approximate Second Quantization Approach

, 2007
The theory of Bogoliubov is generalized for the case of a weakly-interacting Bose-gas in harmonic trap. A set of nonlinear matrix equations is obtained to make the diagonalization of Hamiltonian possible.
Andrij Rovenchak, B. Meini, C.J. Pethick, E.B. Kolomeisky, F. Dalfovo, H. Fu, H. Mukaidani, J.O. Andersen, K.B. Davis, K.V. Kheruntsyan, M. Okumura, M.H. Anderson, M.T. Batchelor, N. Bessis, N.J. Druten van, N.N. Bogoliubov, R. Ozeri, S. Pearson, V. Bagnato, W. Krauth, W.H. Bassichis   +20 more
core   +1 more source

Comment on "Motion of an impurity particle in an ultracold quasi-one-dimensional gas of hard-core bosons [Phys. Rev. A 79, 033610 (2009)]"

, 2010
Very recently Girardeau and Minguzzi [arXiv:0807.3366v2, Phys. Rev. A 79, 033610 (2009)] have studied an impurity in a one-dimensional gas of hard-core bosons. In particular they deal with the general case where the mass of the impurity is different from
Combescot, R., Giraud, S.
core   +1 more source

Phase Coherence and Superfluid-Insulator Transition in a Disordered Bose-Einstein Condensate [PDF]

, 2008
We have studied the effects of a disordered optical potential on the transport and phase coherence of a Bose-Einstein condensate (BEC) of 7Li atoms. At moderate disorder strengths (V_D), we observe inhibited transport and damping of dipole excitations ...
C. Welford, D. Dries, J. Hitchcock, J. W. Goodman, M. Junker, P. W. Anderson, R. G. Hulet, Yong P. Chen   +7 more
core   +3 more sources

Spectral function and quasi-particle damping of interacting bosons in two dimensions

, 2009
We employ the functional renormalization group to study dynamical properties of the two-dimensional Bose gas. Our approach is free of infrared divergences, which plague the usual diagrammatic approaches, and is consistent with the exact Nepomnyashchy ...
A. A. Nepomnyashchy, A. A. Nepomnyashchy, Andreas Sinner, N. N. Bogoliubov, Nils Hasselmann, Peter Kopietz, S. T. Beliaev, S. T. Beliaev, Yu. A. Nepomnyashchy   +8 more
core   +1 more source

Pair Distribution Function of One-dimensional "Hard Sphere" Fermi and Bose Systems

, 2009
The pair distributions of one-dimensional "hard sphere" fermion and boson systems are exactly evaluated by introducing gap variables.Comment: 4 ...
Astrakharchik G. E., Bo-Bo Wei, Castin Y., Cazalilla M., Chen-Ning Yang, Gangardt D. M., Wei B. B. Yang C. N.   +6 more
core   +1 more source