 
Summary: Computational Physics (Computational) : Poster
Pathintegral Monte Carlo study of phonons in the bcc
phase of 4 He
Slava Sorkin 1 , Polturak Emil 1 and Joan Adler 1
, 1 Physics Department, Technion Israel Institute of Technology, Haifa, Israel,
32000
(Submitted by Slava Sorkin , Physics Department, Technion Israel Institute of
Technology, Haifa, Israel, 32000, phsorkin@techunix.technion.ac.il)
Using Path Integral Monte Carlo and the Maximum Entropy method, we calcu
late the dynamic structure factor of solid 4 He in the bcc phase at a finite temperature
of T = 1.6 K and a molar volume of 21 cm 3 . Both the singlephonon contribution
to the dynamic structure factor and the total dynamic structure factor are evalu
ated. From the dynamic structure factor, we obtain the phonon dispersion relations
along the main crystalline directions, [001], [011] and [111]. We calculate both the
longitudinal and transverse phonon branches. We discuss the di#erences between
dispersion relations resulting from the singlephonon part vs. the total dynamic
structure factor. In addition, we evaluate the formation energy of a vacancy.
1
