The polarizability and dynamic structure factor of the 1D Bose gas near the Tonks-Girardeau limit at finite temperatures

Correlation functions related to the dynamic density response of the one-dimensional Bose gas in the model of Lieb and Liniger are calculated. An exact Bose-Fermi mapping is used to work in a fermionic representation with a pseudopotential Hamiltonian. The Hartree-Fock and generalized random phase approximations are derived and the dynamic polarizability is calculated. The results are valid to first order in $1∕\ensuremath{\gamma}$, where $\ensuremath{\gamma}$ is Lieb-Liniger coupling parameter. Approximations for the dynamic and static structure factor at finite temperature are presented. The results preclude superfluidity at any finite temperature in the large-$\ensuremath{\gamma}$ regime due to the Landau criterion. Due to the exact Bose-Fermi duality, the results apply for spinless fermions with weak $p$ -wave interactions as well as for strongly interacting bosons.Correlation functions related to the dynamic density response of the one-dimensional Bose gas in the model of Lieb and Liniger are calculated. An exact Bose-Fermi mapping is used to work in a fermionic representation with a pseudopotential Hamiltonian. The Hartree-Fock and generalized random phase approximations are derived and the dynamic polarizability is calculated. The results are valid to first order in $1∕\ensuremath{\gamma}$, where $\ensuremath{\gamma}$ is Lieb-Liniger coupling parameter. Approximations for the dynamic and static structure factor at finite temperature are presented. The results preclude superfluidity at any finite temperature in the large-$\ensuremath{\gamma}$ regime due to the Landau criterion. Due to the exact Bose-Fermi duality, the results apply for spinless fermions with weak $p$-wave interactions as well as for strongly interacting bosons.

arXiv:cond-mat/0507086Physical Review AFeb 17, 200665 citations

Dynamic structure factor of a Bose-Hubbard gas

TingLi Shao

中国科学通报：英文版Aug 1, 20081 citation

Dynamic structure factor of the one-dimensional Bose gas near the Tonks-Girardeau limit

Joachim Brand, Alexander Yu. Cherny

While the one-dimensional (1D) Bose gas appears to exhibit superfluid response under certain conditions, it fails the Landau criterion according to the elementary excitation spectrum calculated by Lieb. The apparent riddle is solved by calculating the dynamic structure factor of the Lieb-Liniger 1D Bose gas. In a dual representation, strongly interacting bosons are mapped into weakly interacting fermions, which are treated in the Hartree-Fock and generalized random-phase approximations. The dynamic structure factor is calculated analytically in this approximation, which is valid to first order in $1∕\ensuremath{\gamma}$, where $\ensuremath{\gamma}$ is the dimensionless interaction strength of the model. The results clearly indicate a suppression of superfluidity-breaking umklapp excitations near the Tonks-gas limit, which should be observable by Bragg scattering in current experiments.While the one-dimensional (1D) Bose gas appears to exhibit superfluid response under certain conditions, it fails the Landau criterion according to the elementary excitation spectrum calculated by Lieb. The apparent riddle is solved by calculating the dynamic structure factor of the Lieb-Liniger 1D Bose gas. In a dual representation, strongly interacting bosons are mapped into weakly interacting fermions, which are treated in the Hartree-Fock and generalized random-phase approximations. The dynamic structure factor is calculated analytically in this approximation, which is valid to first order in $1∕\ensuremath{\gamma}$, where $\ensuremath{\gamma}$ is the dimensionless interaction strength of the model. The results clearly indicate a suppression of superfluidity-breaking umklapp excitations near the Tonks-gas limit, which should be observable by Bragg scattering in current experiments.

arXiv:cond-mat/0410311Physical Review ASep 28, 200544 citations

A nonideal Bose gas at finite temperatures

Valery Isaakovich Klyatskin

Soviet Physics JournalJan 1, 19661 citation

p

-wave interactions as well as for strongly interacting bosons.