A Technique for Growing Helium Crystals in Preferred Orientations.

Abstract

An apparatus has been developed in which hcp 4He single crystals of high quality are grown with a 0.3 probability of obtaining c-axis orientations of 0 or 90 deg with respect to the direction of growth. Methods of influencing the relative distribution of crystals between these two angles have been observed and are believed to depend on the anisotropy in the thermal conductivity of hcp 4He. A simple computer simulation of the nucleation process supports our identification of the orientation angles and our explanation of the observed orientation preferences. Some possible applications of similar techniques were surveyed. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1973
Accession Number
AD0754442

Entities

People

  • D. T. Lawson

Organizations

  • Duke University

Tags

DTIC Thesaurus Topics

  • Anisotropy
  • Computer Simulations
  • Computers
  • Conductivity
  • Crystals
  • Identification
  • Nucleation
  • Orientation (Direction)
  • Physical Properties
  • Probability
  • Simulations
  • Simulators
  • Single Crystals
  • Thermal Conductivity

Readers

  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.
  • Systems Analysis and Design
  • Thin Film Deposition Science.