Comment on "Symmetry classification of bond order parameters in cuprates"

TL;DR

This paper critiques a previous claim about bond order wave states in cuprates, clarifying the symmetry properties and definitions used in experimental detection, and emphasizing the distinction between different form factor states.

Contribution

It clarifies the transformation properties of bond order waves under symmetries and refutes the claim that certain d-form factor states must be flux states, based on differing definitions.

Findings

The form factors used in experiments differ from those requiring flux state classification.

The paper clarifies the symmetry transformation properties of bond order waves.

It refutes the argument that specific d-form factor states are necessarily flux states.

Abstract

We review the transformation of bond order waves with non-trivial form factors under time-reversal and point group symmetry. Zeyher (arXiv:1406.6846) argues that certain d-form factor states must be "flux states", but this does not apply to the form factors as defined by us (arXiv:1402.4807). The latter definitions were used in the experimental detection (arXiv:1402.5415, arXiv:1404.0362).