Pauli Paramagnetism in Metals with High Densities of States

S. Foner

Francis Bitter National Magnet Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139

 (October 10, 1969)

Because the Pauli paramagnetic susceptibility of a free electron gas, x~ is proportional to the density of states N(O) at the Fermi energy, it is expected that measurements of X~ of metals a nd alloys can yield a reasonable measure of N(O). If xg c an be measured directly, then N(O) can be determined with high accuracy. The major obstacle to this procedure is that the measured static susceptibility Xi, = xV(l-N(O)V)=xgD (for the Stoner model) where V is a measure of the electron-electron interaction potential. Unfortunately, V is not easily determined experimentally, or theoretically, so that measurements of Xv do not yield accurate measures of N(O). More detailed (realistic) models involve additional parameters which are also not accurately determined. Thus direct measurements of Xv can yield a measure of N(O), but these values of N(O) are subject to the uncertainties of various parameters in the theories. In this talk we discuss the present status of experiments and theories of Xv in metals and alloys with low N(O) where D is generally near unity, and high N(O) where D is expected to be large. Comparisons with independent low-temperature electronic specific heat measurements are discussed and attempts to derive N(O) from both susceptibility and specific heat are reviewed.

https://nvlpubs.nist.gov/nistpubs/jres/74A/jresv74An4p567_A1b.pdf