QFS2016 Book of Abstracts

Abstracts

P3.22

Spin-density fluctuations and exchange in normal-liquid

Krotscheck E.(1, 2), Lichtenegger T.(1, 2, 3)

(1) Department of Physics, University at Buffalo, SUNY Buffalo NY 14260,

USA

(2) Institute for Theoretical Physics, Johannes Kepler University, A4040 Linz,

Austria

(3) Department of Particulate Flow Modelling, Johannes Kepler University,

A4040 Linz, Austria

We investigate the dynamics of spin- and density waves of a strongly-correlated,

normal-liquid fermions at absolute zero in two and three dimensions and compare

our results with neutron scattering measurements of the dynamic structure

function in liquid

He. We calculate both the density- and the spin-density

response function at a comparable level of accuracy. Inclusion of intermediate

double-pair states turns out to be essential obtain the energy of both the density

and the paramagnon mode; the resulting dynamic structure function shows

excellent agreement with experiments.

P3.23

Roton states in liquid He4

A.I. Karasevskii

Institute for Metal Physics, 36 Vernadsky boulevard, Kiev 03142, Ukraine

Realization of the nanoparticles rotational degrees of freedom in a melt leads to

an increase in entropy and may causes spontaneous rotation of the nanoparticles.

Rotation of the nanoparticles can also stabilize the phase composition of the

particles and their size [1,2]. In the case of liquid He4 such particles can be

formed as non-equilibrium parts of the crystalline phase (near the melting curve)

or a cluster of normal component in the superfluid phase, the stability of which

is supported by the spontaneous rotation of the nanoparticles. The kinetic and

thermodynamic parameters of the rotonic states of the nanoparticles in a liquid

helium are determined.

] A.I. Karasevskii, Phil. Mag. 95, 1717 (2015).

] A.I. Karasevskii, Metallofiz. Noveishie Tekhnol., 38, 141 (2016) (in Russian).