Electrical Resistivity Of Liquid Metals Research Articles

Electrical resistivity measurement of liquid metals

Two facilities for the complete noninvasive measurement of the electrical resistivity of liquid metals above the melting temperature and in the undercooled liquid state below the melting temperature are presented: a ground-based facility that was built up in our laboratory and the microgravity facility TEMPUS. Both facilities are unique in combining the containerless positioning method of electromagnetic levitation with the contactless, inductive resistivity measurement technique, thereby enabling for the first time measurements in the undercooled liquid state of a metal. The principles and technical realizations of the levitation and measurement technique of both facilities are presented. Furthermore, experimental resistivity data for Cu60Ni40 as well as Co80Pd20 alloy are presented which indicate atomic ordering effects in the undercooled melt.

Electrical Resistivity of Liquid Metals and Alloys

New calculations of resistivities of liquid metals, Na, K, Rb, and alloys, Na-K, Na-Rb, K-Rb, were carried out by using a variant of the Kubo formula that explicitly contains the temperature T. The results come closer to the experiment than the previous ones that use the Ziman formula of resistivity.

The Effect of Local Field Corrections on the Electrical Resistivity of Liquid Metals

en

ELECTRICAL RESISTIVITY OF DISORDERED CRYSTALLINE ALLOYS

The Ziman-type theory of the electrical resistivity of liquid metals is extended to disordered crystalline alloys by means of a prescription given by Baym. The formulae for calculating the resistivity of these systems are presented and the temperature dependence of the resistivity in both low and high temperature range is discussed in some detail. By using the Debye model for lattice vibration, we can express the resisti-vity of a disordered system as ρ=ρ0+ρd(T/Θ)2+ρi(T/Θ)5 at temperatures well below Debye temperature,Θ , this behavior is compatible with experiments. On account of the Debye-Waller factor and multi-phonon effects, the resistivity approaches saturation at high temperature instead of the exhibiting a linear T-dependence predicted by onephonon approximation. A comparison between experimental data and a simple expression derived on the basis of the approximation of independent vibration of atom shows that the deviation from linearity of the high temperature resistivity similar to that of Nb can be understood with the present model.

Electrical Resistivity of Liquid Metals in Regime of Short Mean Free Path

Abstract Using the force-force correlation function formula for electrical resistivity, plus an approximate result of Bardeen for the effect of scattering on the off-diagonal elements of the density matrix, a self-consistent method of calculating the electronic mean free path in liquid metals is proposed.

Modified perturbation theory and the electrical resistivity of simple liquid metals

Abstract The electrical resistivities of the liquid metals Li, Na, K, Be, Mg, Cd, Al and In are calculated using mass-renormalized form factors obtained from optimized model potentials and the modified perturbation theory of Shaw (1969). It is found that renormalizing the form factors leads to marginally better agreement with experimental resistivities for the alkali metals Na and K, but has little effect on the calculated resistivities of polyvalent metals. The effect of renormalizing the prefactors in the Ziman expression for resistivity is also investigated.

Applicability of the T-matrix unitary condition for the electrical resistivity of liquid metals

It is shown that the T-matrix will not satisfy unitarity if one makes the usual assumption of spherical symmetry in the total scattering potential of an electron by an assembly of ions. As a consequence, we show that the importance of multiple scattering remains an open question in the calculation of the electrical resistivity of liquid metals.

Correlation between the strength of the scattering potential and the calculated electrical resistivity of liquid metals

A strong correlation is found between the strength of the scattering potential for the electrons and the deviation of the calculated electrical resistivity from the experimental value. The values found for rho calc/ rho expt are 1.03, 1.04, 0.96, 1.12, 2.4, and 5.3 for Na, K, Al, Pb, Zn and Cd, respectively. These values of rho calc/ rho expt are correlated with the corresponding values for the strength of the scattering potential relative to the kinetic energy of the electron being scattered: 0.04, 0.05, 0.07, 0.15, 0.24, and 0.32. An explanation of this correlation is presented in terms of the criterion for the validity of the Born approximation.

Rotating sample technique for measuring electrical resistivity of liquid metals

A rotating sample technique for measuring the electrical resistivity of liquid metals is developed in some detail and is checked for accuracy and dependability by making measurements of the resistivity of indium-mercury alloys of different compositions. End corrections have been made to the rotating sample method. This method has several advantages over the rotating magnetic field technique that is currently in use. Use of the null technique in this method has allowed us to measure the balancing current in a more precise and reliable way as compared to measuring the deflection of the sample in the rotating magnetic field method.

The electrical resistivity of liquid metals

An expression for the resistivity of a liquid metal is described, which is exactly of the form proposed by Ziman. The advantage over the usual derivation of this formula is that a unique definition of the pseudopotential is possible.

Electrical resistivity of liquid metals in the vicinity of the critical point

In this work we try to develop a model calculation based on the Ziman formula for understanding the dc conductivity of liquid metals at high temperature, in the immediate vicinity of the critical point. We start with a correlation function S( k, ω) and a local electron-ion interaction weighted with the dielectric function ε( k, ω) taken in the random phase approximation. These quantities are considered in the hydrodynamic limit ω → 0, k → 0. Then, it appears that near the critical point, the forward scattering and the resistivity become strongly enhanced by the long range ion-ion correlations. This result remains valid when multiple ionic correlations are taken into account.

Is the Born Approximation Valid for Calculating the Electrical Resistivity of Liquid Metals?

Is the Born Approximation Valid for Calculating the Electrical Resistivity of Liquid Metals?