Magnetic Gr\üneisen Ratio of the Random Transverse-Field Ising Chain

Abstract

The magnetic analog of the Grüneisen parameter, that is, the magnetocaloric effect, is a valuable tool for studying fieldtuned quantum phase transitions. We determine the magnetic Grüneisen parameter of the one-dimensional random transverse-field Ising model, focusing on its low-temperature behavior at the exotic infinite-randomness quantum critical point and in the associated quantum Griffiths phases. We present extensive numerical simulations showing that the magnetic Grüneisen parameter diverges logarithmically with decreasing temperature in the quantum Griffiths phase. It changes sign right at criticality. These results confirm a recent strong-disorder renormalization group theory. We also compare our findings to the behavior of the clean transverse-field Ising chain.

Department(s)

Physics

International Standard Serial Number (ISSN)

0370-1972

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2010 Wiley-VCH Verlag, All rights reserved.

Publication Date

01 Mar 2010

Share

 
COinS