Thermodynamics of Random Ferromagnetic Antiferromagnetic Spin-1/2 Chains

TL;DR

This paper investigates the thermodynamic properties of random ferromagnetic and antiferromagnetic spin-1/2 chains using quantum Monte Carlo simulations, revealing consistent scaling behavior at low temperatures.

Contribution

It introduces a comprehensive numerical analysis of thermodynamic quantities in disordered spin chains and develops a statistical scheme for identifying scaling behavior.

Findings

Consistent scaling behavior observed across multiple thermodynamic quantities.

Supports the conjecture from real-space renormalization group analysis.

Provides a new statistical method for analyzing random spin chain data.

Abstract

Using the quantum Monte Carlo Loop algorithm, we calculate the temperature dependence of the uniform susceptibility, the specific heat, the correlation length, the generalized staggered susceptibility and magnetization of a spin-1/2 chain with random antiferromagnetic and ferromagnetic couplings, down to very low temperatures. Our data show a consistent scaling behavior in all the quantities and support strongly the conjecture drawn from the approximate real-space renormalization group treatment.A statistical analysis scheme is developed which will be useful for the search of scaling behavior in numerical and experimental data of random spin chains.