Correlation-enhanced Friedel oscillations in amorphous alloys and quasicrystals

TL;DR

This paper demonstrates that electron-electron interactions and quantum correlations significantly influence Friedel oscillations in amorphous alloys and quasicrystals, affecting their stability and structural properties.

Contribution

It reveals how quantum correlations induce a divergence in the electron density response, enhancing Friedel oscillations in disordered systems at finite temperatures.

Findings

Power-law divergence of $hi(0,q)$ at $q=2k_F$ due to strong backscattering.

Enhanced and phase-shifted Friedel oscillations observed experimentally.

Potential implications for the stability of icosahedral quasicrystals.

Abstract

We show that quantum correlations induced by electron-electron interactions in the presence of random impurity scattering can play an important role in the thermal stabilization of amorphous Hume-Rothery systems: When there is strong backscattering off local, concentrical ion clusters, the static electron density response $\chi (0,q)$ acquires a powerlaw divergence at $q=2k_F$ even at elevated temperature. This leads to an enhancement as well as to a systematical phase shift of the Friedel oscillations, both consistent with experiments. The possible importance of this effect in icosahedral quasicrystals is discussed.