Fermi Surface Nesting in DisorderedCu1−xPdxAlloys

Abstract

The concentration-dependent position of the diffuse peaks in electron and x-ray diffraction patterns of Cu1-xPdx alloys in the disordered state is attributed to Fermi surface nesting. We present the first experimentally determined Fermi surfaces of Cu0.72Pd0.28 and Cu0.6Pd0.4, and show that they do indeed possess significant flat areas capable of nesting. Moreover, the magnitudes of the nesting vectors are in excellent agreement with those deduced from electronic structure calculations and diffraction experiments.

Anomalous magnetic properties in Ni50Mn35In15

“…The reason for the step /kink is believed to be the trapping of electrons in the nested regions of the Fermi surface due to long range structural ordering formed as a consequence of martensitic phase change. And the nesting vector corresponds to the modulation of martensite formed [20,21,22]. However, after the transformation is complete, ρ in the martensitic phase can be extrapolated to match with the curve obtained before the transition had occurred.…”

Evolution of the Fermi surface and the oscillatory exchange coupling across Cr and Cr-based alloys

“…This well-established technique has recently been used by some of the present authors to determine the FS topology and identify nesting features in a wide range of systems. [21][22][23] The virtue of the 2D-ACAR technique in such studies is that it reveals directly the shape of the FS.…”

Nonlocal spectral properties of disordered alloys

“…However, only the periodic set of cluster momenta {K n } are used and no attempt is made to remove the discontinuities. It is our intention to combine the method in this paper with the formalism of [25], and investigate the effects of SRO on Fermi surface features of systems such as CuP d [11].…”

“…Moreover, these 'rounding' and 'squaring' features of Fermi surfaces not seen in the CPA calculations have been observed experimentally. For example, the work of Wilkinson et al [11] gives a clear example for Cu 1−x P d x where the diamond-like Fermi surface on the (100) plane predicted by the KKR-CPA is actually found experimentally to be rounded. Furthermore, smearing and the associated width of peaks regains a k-dependence that produces so-called 'hotspots' along the Γ − X directions as shown by dark patches in the difference between the CPA and mixed NLCPA.…”