Pressure dependence of the electron-phonon interaction derived from normal state resistivity: Al and Pb (original) (raw)

1978, Solid State Communications

The electrical resistance of Li, Pd, Au, and Pb is measured as a function of temperature and pressure in the region-20'C to + 30'C and 0-1.3 GPa. Self-consistent linear muffin-tin orbital band-structure calculations of these elements and of Al are performed at normal and reduced volumes. Results are obtained for the density of states N (EF), the average Fermi velocity, the optical mass, the plasma frequency co, and the volume dependence of these parameters. The pressure dependence of the electron-phonon interaction A, (p) is obtained from these measurements and the calculated co(p). For the superconducting elements there is good agreement with the measured superconducting T,(p). Results from our previous measurements and calculations on Al, V, Nb, and La and published results for co(p) are included in this comparison. A, (p) increases with pressure for bcc Li and decreases for Pd and Au. Pressure is expected to suppress spin fluctuations much faster than A, (p) in Pd. The possibility of inducing superconductivity by pressure in Pd and bcc Li is discussed. The electronic Gruneisen parameter y, is obtained from A, (p) and the volume dependence of N(EF). Comparison with other results for y, generally shows good agreement. the measurements are described and the results are presented and analyzed. The band-structure calculation is described in Sec. IV. We obtain results for the volume dependence of the plasma frequency and some other average Fermi-surface properties, i.e. , the Fermi velocity, the optical mass, and the density of states N(Ez). The results for A, (p) are presented and discussed in Sec. V. Having obtained the volume dependence of N(EF) as well as A, , it is useful to compare them with the electronic Gruneisen parameter y,. This is briefly discussed in Sec. VI. The main conclusions are summarized in Sec. VII.