Accession Number:

AD0256801

Title:

PRESSURE DEPENDENCE OF THE HALL CONSTANT OF THE ALKALI METALS

Descriptive Note:

Corporate Author:

HARVARD UNIV CAMBRIDGE MASS GORDON MCKAY LAB

Personal Author(s):

Report Date:

1960-07-01

Pagination or Media Count:

1.0

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 kgsq cm. In each case the Hall voltage decreased with increasing pressure, the size of the decrease ranging from 2 in 15,000 kgsq cm for Li to 37 in 15,000 kgsq 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

Subject Categories:

Distribution Statement:

APPROVED FOR PUBLIC RELEASE