Off-shell selfenergy for 1-D Fermi liquids

The selfenergy in Born approximation including exchange of interacting one-dimensional systems is expressed in terms of a single integral about the potential which allows a fast and precise calculation for any potential analytically. The imaginary part of the self energy as damping of single-particle excitations shows a rich structure of different areas limited by single-particle and collective excitation lines. The corresponding spectral function reveals a pseudogap, a splitting of excitation into holons and antiholons as well as bound states

Study of weakly interacting trapped Bose gas

We have obtained expressions for single particle density and two particle density of weakly interacting trapped quantum gases. These are valid for all temperature and in any dimension. These expressions have been simplified and expressed in terms of non-interacting single particle density. The ground fluctuations for T<Tc in grand canonical ensemble has been treated with care using the method of Kocharovsky et al. [Phys. Rev. A 61, 053606 (2000)]. Some numerical results are presented in one and three dimension for isotropic harmonically trapped Bose gas with contact interactions. It is seen that boson density decreases with increasing repulsive interactions. The expression for critical temperature is also shown to agree with earlier result and is in accordance with experiments

Particle density and transition temperature of weakly interacting quantum gases

An expression for single particle density of weakly interacting trapped quantum gases has been obtained for Fermi gas at all temperatures and for Bose gas above the transition temperature (Tc). This expression has been used to study the effect of interaction on density of harmonically trapped Bose gas. It is found that interaction has a large effect on the density at centre of the trap as observed experimentally. The same expression for density is also used to obtain the transition temperature of homogeneous Bose gas. Experimental results for Tc has been re-analysed on the basis of perturbative and non-perturbative theories. It is found that both the theories fit experimental data equally well in low-density regimes

Erratum to: Particle density and transition temperature of weakly interacting quantum gases

An expression for single particle density of weakly interacting trapped quantum gases has been obtained for Fermi gas at all temperatures and for Bose gas above the transition temperature (Tc). This expression has been used to study the effect of interaction on density of harmonically trapped Bose gas. It is found that interaction has a large effect on the density at centre of the trap as observed experimentally. The same expression for density is also used to obtain the transition temperature of homogeneous Bose gas. Experimental results for Tc has been re-analysed on the basis of perturbative and non-perturbative theories. It is found that both the theories fit experimental data equally well in low-density regimes