Damping of Nodal Fermions Caused by a Dissipative Mode

TL;DR

This paper demonstrates that in a 2+1 dimensional d-wave superconductor, dissipative excitations replace Nambu Goldstone modes, leading to linear-in-frequency damping of nodal quasiparticles, aligning with recent experimental observations.

Contribution

It reveals that dissipative modes dominate over Goldstone fluctuations in 2+1D d-wave superconductors, altering quasiparticle damping behavior.

Findings

Nodal quasiparticle damping is caused by dissipative excitations.

Scattering rates are linear in frequency, not cubic.

Results explain recent ARPES and optical conductivity data in BSCCO.

Abstract

Using a $d_{x^2 - y^2}$ superconductor in 2+1 dimensions we show that the Nambu Goldstone fluctuations are replaced by dissipative excitations. We find that the nodal quasi-particles damping is caused by the strong dissipative excitations near the nodal points. As a result we find that the scattering rates are linear in frequency and not cubic as predicted in the literature for the ``d'' wave superconductors. Our results explain the recent angle resolved photoemission spectroscopy and optical conductivity in the BSCCO high $T_c$ compounds.