Accession Number : AD0254580

Title :   IMAGE OF THE FERMI SURFACE IN SPIN WAVE SPECTRA OF RARE EARTH METALS

Corporate Author : CALIFORNIA UNIV SAN DIEGO LA JOLLA

Personal Author(s) : WOLL, EDWIN J. JR. ; NETTEL, STEPHEN J.

Report Date : 1960

Pagination or Media Count : 1

Abstract : Calculations of spin wave spectra in rare earth metals were conducted to find whether images of the electronic Fermi surface might be observable. In the space of spin wave vectors q there should occur surfaces on which the frequencies have an infinite gradient with respect to q, the location of such abrupt changes, kinks in the dispersion curves, being determined by the shape of the Fermi surface. The spin wave spectrum is found by assuming that the coupling between ionic spins takes place primarily through exchange scattering of conduction electrons, paralleling the calculation of the coupling of nuclear spins by Ruderman and Kittel (Phys, Rev. 96:99, 1954). Spin wave dispersion curves in two directions of high symmetry are computed numerically. The sought-for kinks in the dispersion curves amounted to about 2% of the maximum excitation frequency. The development is for ferromagnets, but extension to spiral antiferromagnets is taken up briefly. (Author)

Descriptors :   *NUCLEAR SPINS, *RARE EARTH ELEMENTS, ANTIFERROMAGNETISM, ATOMIC ENERGY LEVELS, BRILLOUIN ZONES, CRYSTAL STRUCTURE, CRYSTALS, ELECTRONS, FERROMAGNETIC MATERIALS, MAGNETIC PROPERTIES, MATHEMATICAL ANALYSIS, NUMERICAL ANALYSIS, SURFACES.

Distribution Statement : APPROVED FOR PUBLIC RELEASE