Related papers: Dynamic Structure Function in 3he-4he Mixtures
On the basis of the expression for the density matrix of interacting Bose particles in the coordinate representation with regard for the direct three- and four-particle correlations [I.O.\,\,Vakarchuk and O.I.\,\,Hryhorchak,…
We have studied solid hydrogen up to pressures of 300 GPa and temperatures of 350 K using density functional theory methods and have found "mixed structures" that are more stable than those predicted earlier. Mixed structures consist of…
We investigate the collective excitations of $^3$He-$^4$He mixture films at zero temperature within random phase approximation and linear response theory. In low concentration region of $^3$He, a level repulsion between zero sound and third…
Molecular dynamics results for the dynamic structure of a He0.77Ne0.23 gas mixture at two densities (15.8 nm-3 and 36.1 nm-3) are presented. A clear description of the crossover from hydrodynamic modes to distinct excitations for the two…
A detailed discussion of the coherent and incoherent dynamic structure function of the free Fermi gas at finite temperature is presented. Their behavior and evolution with the momentum transfer and the temperature is analyzed, while…
A molecular dynamics simulation is performed to investigate spatial scale of low energy excitation (LEE) in a single linear chain of united atoms. The self part of the dynamic structure function, $S_\mathrm{S}(q,\omega)$, is obtained in a…
Both isoscalar and isovector spin-dipole excitations of $^4$He are studied using realistic nuclear forces in the complex scaling method. The ground state of $^4$He and discretized continuum states with $J^{\pi}=0^-, 1^-, 2^-$ for A=4 nuclei…
We have carried out a microscopic study of the dynamic structure factor of liquid $^4$He across the normal-superfluid transition temperature using the path integral Monte Carlo method. The ill-posed problem of the inverse Laplace transform,…
We develop a linked cluster method to calculate the spectral weights of many-particle excitations at zero temperature. The dynamical structure factor is expressed as a sum of exclusive structure factors, each representing contributions from…
We develop a systematic theory of multi-particle excitations in strongly interacting Fermi systems. Our work is the generalization of the time-honored work by Jackson, Feenberg, and Campbell for bosons, that provides, in its most advanced…
The dynamic structure factor and the eigenmodes of density fluctuations in the uniform liquid $^3$He are studied using a novel non-perturbative approach. This new version of the self-consistent method of moments invokes up to nine sum rules…
We calculate the dynamic structure factor S(k,omega) of liquid Ge (l-Ge) at temperature T = 1250 K, and of amorphous Ge (a-Ge) at T = 300 K, using ab initio molecular dynamics. The electronic energy is computed using density-functional…
Based on the theoretical framework of generalized eikonal approximation we study the two-nucleon emission reactions in high $Q^2$ electro-disintegration of $^3He$. Main aim is to investigate those features of the reaction which can be…
The dynamic structure function $S(k,\omega)$ informs about the dispersion and damping of excitations. We have recently (Phys. Rev. B {\bf 97}, 184520 (2018)) compared experimental results for $S(k,\omega)$ from high-precision neutron…
We present extensive new \emph{ab initio} path integral Monte Carlo (PIMC) simulations of normal liquid $^3$He without any nodal constraints. This allows us to study the effects of temperature on different structural properties like the…
We present measurements of the dynamical structure factor $S(q,\omega)$ of an interacting one-dimensional (1D) Fermi gas for small excitation energies. We use the two lowest hyperfine levels of the $^6$Li atom to form a pseudo-spin-1/2…
We present a theoretical study of the dynamic structure function of a resonantly interacting two-component Fermi gas at zero temperature. Our approach is based on dynamic many-body theory able to describe excitations in strongly correlated…
We present an ab-initio calculation of the longitudinal electron scattering response function off 4He with two- and three-nucleon forces and compare to experimental data. The full four-body continuum dynamics is considered via the Lorentz…
We use a dispersion relation in conjunction with the operator product expansion (OPE) to derive model independent sum rules for the dynamic structure functions of systems with large scattering lengths. We present an explicit sum rule for…
Using neutron scattering, we investigate the static and dynamic structure functions $S(Q,\omega)$ of 3 distinct solid phases (using powder average techniques), and characterize the corresponding modes of energy excitation, focusing…