Comment on "Evidence for a small hole pocket in the Fermi surface of underdoped YBa2Cu3Oy; [arXiv:1409.2788v1]"

TL;DR

This paper critiques experimental findings on small hole pockets in underdoped YBa2Cu3Oy, suggesting the results align better with a unidirectional charge density wave model with alternating vector directions along the c-axis.

Contribution

It offers a reinterpretation of previous experimental data, proposing a unidirectional CDW with alternating directions as a more consistent explanation.

Findings

Supports unidirectional CDW model with alternating vector directions

Challenges the interpretation of small hole pockets as evidence of Fermi surface reconstruction

Suggests charge order vector orientation is key to understanding Fermi surface features

Abstract

N. Doiron-Leyraud et al. in [1] report on the experimental observation of small holes pockets in the energy spectrum of YBa2Cu3Oy (YBCO) coming below the transition into the charge ordered (CO) phase as a result of a Fermi surface (FS) reconstruction. We comment that their results seem to be more consistent with a unidirectional charge density wave (CDW) vector direction of which alternates along the c-axis between neighboring CuO2 -planes.