Screening of particle exchange in quantum Boltzmann liquids

Abstract

We employ correlated density-matrix theory of strongly correlated Bose fluids to analyze the structural properties of quantum Boltzmann liquids. The constituents of such a normal quantum system are distinguishable as in a classical fluid since the interparticle forces prevent any exchange of identical bosons at short relative distances. Our study focuses on this particle-screening effect and on its consequences for the properties of various correlation functions, structure functions, momentum distributions, and quasiparticle and collective excitations. The formalism of the adopted microscopic theory is applied to a detailed numerical investigation of particle-screening properties and the quantum behavior of liquid para-hydrogen close to the triple point temperature. The theoretical results are compared with numerical data of path-integral Monte Carlo simulations and with available experimental results of recent cross-section measurements by neutron scattering.