Conductance of a tunnel point-contact of noble metals in the presence of a single defect

TL;DR

This paper develops a new algorithm to compute the conductance oscillations of noble metal tunnel contacts with a single defect, considering Fermi surface anisotropy, and predicts observable patterns via scanning tunneling microscopy.

Contribution

It introduces an original algorithm for calculating conductance with arbitrary Fermi surfaces and applies it to noble metals, extending previous theoretical work.

Findings

Conductance oscillations depend on Fermi surface geometry.

Patterns of conductance oscillations vary with surface orientation.

The method enables predictions for STM experiments.

Abstract

In paper [1] (Avotina et al. Phys. Rev. B,74, 085411 (2006)) the effect of Fermi surface anisotropy to the conductance of a tunnel point contact, in the vicinity of which a single point-like defect is situated, has been investigated theoretically. The oscillatory dependence of the conductance on the distance between the contact and the defect has been found for a general Fermi surface geometry. In this paper we apply the method developed in [1] to the calculation of the conductance of noble metal contacts. An original algorithm, which enables the computation of the conductance for any parametrically given Fermi surface, is proposed. On this basis a pattern of the conductance oscillations, which can be observed by the method of scanning tunneling microscopy, is obtained for different orientations of the surface for the noble metals.