S.P. Hörnfeldt

The Fermi surface of antimony from magneto-acoustic resonances

Geometric resonances and deHaas-van Alphen type oscillations in ultrasonic attenuation at 150 Mcsec give a Fermi surface of antimony consisting of three electron ellipsoids tilted by 35° each containing 1.40 × 1025electronsm3 and three hole ellipsoids each containing 1.46 × 1025holesm3. Comparison with available information in literature from cyclotron resonances give Fermi energies of 18 × 10−21 J and 13 × 10−21 J respectively.

The hole pockets of the Fermi surface in iridium from the De Haas-Van Alphen effect

Abstract Extreme area data for the X-centered d-band hole pockets in iridium are presented. The areas of the larger X-centered pockets X2 are in agreement with the areas calculated by Andersen and Mackintosh. The effective masses of X2 give a mass enhancement of 1.4.

The De Haas-van Alphen effect and the Fermi surface in iridium

Abstract The two sets of X -centered hole pockets of the Fermi surface in iridium have been studied by means of the de Haas-van Alphen effects using field modulation technique. The extreme areas have been determined with the direction of the magnetic field in two different crystallographic planes. The areas obtained were inverted into radii. The contributions to the carrier concentration were found to be 0·0068±0·0001 states/atom and 0·078±0·002 states/atom for the two sets of hole pockets respectively. From effective mass measurements the contributions to the density of states at the Fermi level were estimated to 0·37±0·03 and 3·2±0·3 states/atom/Rydberg for the two sets.

Parallel field magnetoacoustic effect in antimony

Abstract Oscillations in the acoustic attenuation in antimony are measured with longitudinal sound waves and magnetic field⋅parallel to the 3-fold axis. The result is interpreted as oscillations in the field direction of electrons belonging to extremum orbits of the titled Shoenberg ellipsoids.

Itinerant magnetization in dilute Pt(Ni) and Pt(Fe)

Abstract The Zeeman splitting of conduction electrons in platinum with nickel or iron impurities has been studied using the de Haas-van Alphen effect. It is found that 200 ppm iron increases the Zeeman splitting by about 15%, while nickel up to 2000 ppm has no detectable influence on the Zeeman splitting.

Measurement of the conduction electron Zeeman splitting in platinum

Abstract The cyclotron orbit g -factor in platinum has been investigated using the de Haas-van Alphen effect. Several new features of the spin splitting zero (SSZ) contours of the Γ-centered electron sheet have been established. Six closed spin splitting zero contours of the fundamental of this sheet have been mapped out together with several branches of spin splitting zero contours of the second harmonic. The results give an almost complete determination of the anisotropy of the cyclotron orbit g -factor of the Γ-centered electron sheet in platinum.

Precision measurements of some dHvA frequencies in iridium

Abstract A method to perform presicion determinations of de Haas—van Alphen frequencies using the precise values of the de Haas—van Alphen frequencies of gold as reference, is described. Data for orbits in the [100] and [110] directions of iridium are presented.

Zeeman splitting of conduction electrons in nickel-doped palladium

Abstract The ratio between the Zeeman splitting and the Landau level spacing of the electrons at the Fermi level in palladium is found to be strongly dependent on nickel impurities.

Measurements of the conduction electron g-factor in platinum

Abstract The anisotropy of the cyclotron orbit g -factor in platinum has been studied through mapping out spin splitting zero contours of the fundamental and second harmonic on the Γ-centered electron sheet using the de Haas-van Alphen effect. Several new features of the spin splitting zero contours of the fundamental have been established.

De Haas-van Alphen effect in rhodium

The de Haas-van Alphen effect has been used to study the extremal areas and effective cyclotron masses on all five sheets of the Fermi surface of rhodium for the magnetic field in a (110)-plane. The measured extremal areas are in good agreement with relativistic-augmented-plane-wave calculations. The resulting deviations correspond to energy shifts of the calculated bands not exceeding 4 mRy. Several extremal orbits on the fifth band Γ-centered electron sheet have been observed. The mass enhancement determined from the ratio between the calculated and measured effective cyclotron masses is found to vary substantially over the different sheets of the Fermi surface. A rather isotropie factor of 1.40 is obtained for the sixth band Γ-centered electron sheet. For the third and fourth band hole pockets we obtained enhancement factors in the region 0.9–1.4.