Comment on "Anomalous Thermal Conductivity of Frustrated Heisenberg Spin Chains and Ladders"

TL;DR

This paper critiques a recent numerical study on thermal conductivity in frustrated spin chains and ladders, arguing that their conclusion of finite Drude weight in the thermodynamic limit is not supported when larger system sizes are considered.

Contribution

It challenges previous findings by analyzing larger system sizes, suggesting the finite Drude weight conclusion may not hold in the thermodynamic limit.

Findings

Finite-size analysis may overestimate Drude weight.

Larger system sizes indicate the Drude weight may vanish.

Previous conclusions are not conclusive for thermodynamic limit.

Abstract

In a recent letter [Phys. Rev. Lett. 89, 156603 (2002); cond-mat/0201300], Alvarez and Gros have numerically analyzed the Drude weight for thermal transport in spin ladders and frustrated chains of up to 14 sites and have proposed that it remains finite in the thermodynamic limit. In this comment, we argue that this conclusion cannot be sustained if the finite-size analysis is taken to larger system sizes.