Uniaxial stress and strain derivatives of the Fermi-surface necks in gold

Abstract

Simultaneous measurements of quantum oscillations in magnetostriction and torque in a single crystal of gold have been used to determine precise values for the derivatives of the cross-sectional area of the [111] neck of the Fermi surface with respect to uniaxial tensile stress along the [110] and [Formula: see text] directions. Independent estimates of the derivative with respect to uniaxial tensile stress along [111] of the neck area have been deduced from appropriate combinations of the [110] and [Formula: see text] stress derivatives with the established hydrostatic-pressure derivative. These estimates are in excellent agreement, giving ∂ lnA111/∂σ111 = (11.5 ± 0.3) × 10−12cm2∙dyn−1 (1 dyn = 10 μN). This result is significantly larger than the result of early direct-tension measurements in gold, suggesting that the latter suffered from systematic error. The present result is consistent with, and more precise than, earlier magnetostriction and direct uniaxial compression data. The angular shear derivative ∂ ln A/∂γ = 5.56 ± 0.17, deduced from the present data, is slightly larger than the theoretical value of 4.80 ± 0.20 obtained from a relativistic Korringa–Kohn–Rostoker phase-shift calculation based a rigid spherical muffin-tin pseudopotential.