English

Extraction of the Spin Glass Correlation Length

Disordered Systems and Neural Networks 2009-10-31 v2 Statistical Mechanics

Abstract

The peak of the spin glass relaxation rate, S(t)=d{-M_{TRM}(t,t_w)}/H/{d ln t}, is directly related to the typical value of the free energy barrier which can be explored over experimental time scales. A change in magnetic field H generates an energy E_z={N_s}{X_fc}{H^2} by which the barrier heights are reduced, where X_{fc} is the field cooled susceptibility per spin, and N_s is the number of correlated spins. The shift of the peak of S(t) gives E_z, generating the correlation length, Ksi(t,T), for Cu:Mn 6at.% and CdCr_{1.7}In_{0.3}S_4. Fits to power law dynamics, Ksi(t,T)\propto {t}^{\alpha(T)} and activated dynamics Ksi(t,T) \propto {ln t}^{1/psi} compare well with simulation fits, but possess too small a prefactor for activated dynamics.

Keywords

Cite

@article{arxiv.cond-mat/9809246,
  title  = {Extraction of the Spin Glass Correlation Length},
  author = {Y. G. Joh and R. Orbach and G. G. Wood and J. Hammann and E. Vincent},
  journal= {arXiv preprint arXiv:cond-mat/9809246},
  year   = {2009}
}

Comments

4 pages, 4 figures. Department of Physics, University of California, Riverside, California, and Service de Physique de l'Etat Condense, CEA Saclay, Gif sur Yvette, France. To appear in Phys. Rev. Lett. January 4, 1999