Proefschrift-Utrecht.

Proefschrift Leiden. / Met lit. opg.

Proefschrift--Leyden. Rijksuniversiteit. / Includes bibliographical references.

No description available.

Stuttgart, Univ., Diss., 2001.

Konstanz, Univ., Diss., 2001.

Zugl.: Dresden, Techn. Univ., Diss., 2010

<p> The de Haas-van Alphen effect has been used to measure the Fermi surface areas, cyclotron masses and Dingle temperatures in antimony and its alloys containing less than 0.3 percent tin. The Fermi surface of each alloy was similar to the pure antimony surface. However the hole surface increased in size and the electron surface shrunk since tin removes electrons from the alloy. The cyclotron masses increased and decreased for holes and electrons respectively, giving a definite indication of nonparabolic conduction and valence bands. The cyclotron masses were found from the temperature dependence of the dHvA amplitude after interfering dHvA frequency components were removed by a Fourier analysis technique. The Dingle temperature increased roughly linearily with tin concentration.</p> <p> A comparison of the hole and electron Fermi surface volumes with the number of tin atoms added to the alloys shows that one tin atom removes one electron from the alloy as expected from the unit valence difference between antimony and tin. This value is higher than that found by other workers using different techniques.</p> <p> The shapes of the energy bands along with the cyclotron masses have been compared with several band models. An ellipsoidal band provides a rough overall description of both holes and electrons while an ellipsoidal nonparabolic band describes the mass behaviour on alloying more accurately. A pseudopotential band calculated using the method and potential of Falicov and Lin (1967) was also compared with the data.</p> <p> The observed relative frequency changes were used to compare the data with the rigid band model of alloying. The bands are rigid for low concentrations. At higher concentrations there are deviations apparently caused by the cyclotron mass change and an axial ratio change in the hole Fermi surface.</p> / Thesis / Doctor of Philosophy (PhD)

<p> The de Haas-van Alphen (dHvA) effect has been studied in single crystals of calcium using the modulation method in magnetic fields up to 55 kOe. Four distinct orbits were observed with dHvA frequency minima at the [110] or [100] directions. The results do not support calculations predicting a disconnected first-band Fermi surface for calcium. The dHvA data of crystalline calcium is consistent with the topology of the two-OPW model in which the first band is connected and pockets of electrons are about the point L of the second zone.</p> / Thesis / Master of Science (MSc)

A digital program has been developed to Fourier analyse the data obtained in experiments to study the de Haas-van Alphen effect. A physical account of the origin of this effect is given and the problem of analysing the data is explained. An account is given of the development of the program together with a consideration of the mathematical properties of the Fourier transform. General questions concerning the resolving power and accuracy of this method of analysis are discussed. The program was tested using artificial synthetic data of known analytic form and later applied to the analysis of data from a single crystal of mercury. / Thesis / Master of Science (MSc)