PRESSURE DEPENDENCE OF THE HALL CONSTANT OF THE ALKALI METALS

Abstract

Recent band structure calculations indicate how the Fermi surface of the alkali metals, which is expected to be nearly spherical under normal conditions, may change when the lattice constant is decreased through hydrostatic pressure. Since direct measurement of the distortion of the Fermi surface is difficult, attempts were made to study its magnitude by measuring the Hall voltage in the alkalis as a function of hydrostatic pressure up to 15,000 kg/sq cm. In each case the Hall voltage decreased with increasing pressure, the size of the decrease ranging from 2% in 15,000 kg/sq cm for Li to 37% in 15,000 kg/sq cm for Cs before compressibility corrections are applied. The pressure results are explained in a semi-quantitative manner using a scattering time that varies by a factor of three over the Fermi surface. By contrast, the warping of the Fermi surface is small; with the exception of Cs, the electron wave vector at the Fermi surface deviates from the free electron value by less than 10%. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1960
Accession Number
AD0256801

Entities

People

  • Thomas Frederick Deutsch

Organizations

  • Harvard University

Tags

DTIC Thesaurus Topics

  • Alkali Metals
  • Band Structures
  • Electrons
  • Energy Bands
  • Fermi Surfaces
  • Free Electrons
  • Hydrostatic Pressure
  • Measurement
  • Metals

Fields of Study

  • Physics

Readers

  • Mathematics or Statistics
  • Molecular Photonics/Laser Physics
  • Semiconductor Device Technology

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene