Signature of Spin Collective Mode in Local Tunneling Spectra of a d-wave Superconductor

TL;DR

This paper investigates how magnetic excitations affect the local density of states in a d-wave superconductor, revealing periodic modulations that do not match experimental observations, thus providing insights into the magnetic influences on quasiparticle spectra.

Contribution

The study models magnetic susceptibility within the renormalized t-t'-J framework and analyzes its impact on quasiparticle self-energy and LDOS modulations, offering a theoretical perspective on magnetic effects in superconductors.

Findings

LDOS exhibits periodic components along specific directions.

Wavevector magnitudes vary with quasiparticle energy.

Theoretical LDOS modulations do not align with experimental data.

Abstract

We consider the influence of magnetic excitations on the local density of states in the d-wave superconductor. The magnetic susceptibility is calculated within the renormalized $t-t'-J$ model and its influence on the quasiparticle self-energy is considered using a minimal model originally proposed by Polkovnikov {\it et al.}[cond-mat/0203176]. We find the local density of states possess periodic components both along $(\pi,0)$ and $(\pi,\pi)$ directions with the associated wavevectors changing in magnitude as the quasiparticle energy is varied. Comparison with the STM experiment reveals that the calculated LDOS modulation is inconsistent with the measured data.