We propose the ``pair-breaking scattering interference" as a general source of coherence peak modulations in superconductors. Assuming this mechanism, we present a simple physical picture for the coherence peak modulations in overdoped cuprate Bi2Sr2Ca2Cu3O10+δ (Bi-2223), ferromagnetic iron pnictide EuRbFe4As4 (Eu-1144), and kagome metals AV3Sb5 (A= K, Rb, and Cs). Specifically, we explain the wavevectors, the particle-hole symmetry, and the dependence on the internal or external Zeeman-field of the coherence peak modulations. This work is intended as a cautious reminder to the scientific community when asserting the existence of a pair density wave phenomenon in the absence of tunneling conductance modulations in the normal state.
@article{arxiv.2310.06024,
title = {Pair-breaking scattering interference as a mechanism for superconducting gap modulation},
author = {Zhi-Qiang Gao and Yu-Ping Lin and Dung-Hai Lee},
journal= {arXiv preprint arXiv:2310.06024},
year = {2024}
}