Quasiparticle scattering and local density of states in graphite

TL;DR

This paper investigates how quasiparticle interference affects the local density of states in graphite near impurities, providing insights into Fermi liquid behavior and implications for understanding cuprate superconductors.

Contribution

It offers a detailed analysis of quasiparticle interference effects on LDOS in graphite and compares theoretical results with STM experiments to test Fermi liquid applicability.

Findings

Identification of characteristic interference behaviors in Fourier spectra

Potential validation of Fermi liquid theory in graphite through experimental comparison

Insights into similarities between graphite and cuprate superconductor quasiparticles

Abstract

We determine the effect of quasiparticle interference on the spatial variations of the local density of states (LDOS) in graphite in the neighborhood of an isolated impurity. A number of characteristic behaviors of interference are identified in the Fourier transformed spectrum. A comparison between our results and scanning tunneling microscopy (STM) experiments could provide a critical test of the range (of energy) of applicability of the Fermi liquid description of graphite, where some evidence of the breakdown of Fermi liquid theory has recently been discussed. Moreover, given the similarity between the band structures of graphite and that of nodal quasiparticles in a d-wave superconductor, a comparison between results in the two materials is useful for understanding the physics of the cuprates.