Thermopower and resistivity due to dislocations in monovalent metals

Abstract

Using the partial-wave method, the residual electrical resistivity and the additional and characteristic thermopowers of dislocations for noble and alkaline metals are calculated. Just the scattering of electrons by the dislocation core is considered. The existence of resonance electron states near the Fermi energy within the thermal scatter kBT is supposed. The lattice dilatation ΔV = bB2 (bB is the steady Burgers vector) is taken into account. Various forms of rectangular potential simulating the dislocation core are investigated. It is shown that unlike the dislocation resistivity, the thermoelectric characteristic of dislocations shows high sensitivity to change of the width of the resonance level and its localization relative to the Fermi energy. A model dislocation potential is suggested; with it, a rather good agreement with available experimental data is obtained.

Thermopower due to defects in Ni, Pd and Pt

“…As shown in [7], the scattering cross section and residual resistivity of dislocation are weakly sensitive to the choice of the parameter. Below it will be shown that calculated additional thermopower per unit dislocation density is insensitive to the choice of the radius R 1 as well if the height of the potential barrier V 0 is determined self-consistently from the Fridel screening…”

“…The thermopower change per unit concentration of vacancies [1,2] and dislocations [3] has been determined; the characteristic thermopower induced by dislocations has been estimated [4]. The results of measurements are in good correlation with the calculated contribution of vacancies and dislocations to the thermopower of noble metals [5][6][7].…”

Quantized dislocations

“…The electrical transport in dislocated materials has been extensively studied both theoretically [34][35][36][37][38][39][40][41][42][43][44][45][46][47] and experimentally [48][49][50][51][52][53][54], in both semiconductors [34,35,[38][39][40][41]48,53,55] and metals [36,[42][43][44]47,[49][50][51]54]. A few most prominent studies share a common feature, that to develop a theoretical model first, followed by experimental measurements, with a focus on the carrier mobility and electrical resistivity [34,[38][39][40]44,52,55].…”

“…For metals, one may naturally expect that the deformation potential scattering equation ( 6) is the main mechanism that accounts for electron-dislocation interaction, yet the situation is complicated by the resonant scattering between electrons near the Fermi surface and the dislocation core [37,[43][44][45]48]. One intuitive understanding of such resonance may arise from the comparable, sub-nm scale between the Fermi wavelength of the electrons and the dislocation core size [60].…”

“…Fortunately, a much simpler solution has been found [202]. Instead of imposing equation (48), which is equivalent to a k , a + q = δ kq , a different commutation condition:…”