Study of solid 4He in two dimensions. The issue of zero-point defects and study of confined crystal

Details Study of solid 4He in two dimensions. The issue of zero-point defects and study of confined crystal Study of solid 4He in two dimensions. The issue of zero-point defects and study of confined crystal

2012-03-21

arxiv.org/abs/1203.4747v1

Physics

Condensed Matter

Statistical Mechanics

17 pages, accepted for publication in J. Low Temp. Phys., Special Issue on Supersolids

Scientific paper

Defects are believed to play a fundamental role in the supersolid state of 4He. We report on studies by exact Quantum Monte Carlo (QMC) simulations at zero temperature of the properties of solid 4He in presence of many vacancies, up to 30 in two dimensions (2D). In all studied cases the crystalline order is stable at least as long as the concentration of vacancies is below 2.5%. In the 2D system for a small number, n_v, of vacancies such defects can be identified in the crystalline lattice and are strongly correlated with an attractive interaction. On the contrary when n_v~10 vacancies in the relaxed system disappear and in their place one finds dislocations and a revival of the Bose-Einstein condensation. Thus, should zero-point motion defects be present in solid 4He, such defects would be dislocations and not vacancies, at least in 2D. In order to avoid using periodic boundary conditions we have studied the exact ground state of solid 4He confined in a circular region by an external potential. We find that defects tend to be localized in an interfacial region of width of about 15 A. Our computation allows to put as upper bound limit to zero--point defects the concentration 0.003 in the 2D system close to melting density.

Affiliated with

Also associated with

No associations

Rating

Study of solid 4He in two dimensions. The issue of zero-point defects and study of confined crystal does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Study of solid 4He in two dimensions. The issue of zero-point defects and study of confined crystal, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Study of solid 4He in two dimensions. The issue of zero-point defects and study of confined crystal will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-488709