Effect of disorder on quantum phase transitions in anisotropic XY spin chains in a transverse field

Details Effect of disorder on quantum phase transitions in anisotropic XY spin chains in a transverse field Effect of disorder on quantum phase transitions in anisotropic XY spin chains in a transverse field

1998-12-31

arxiv.org/abs/cond-mat/9812430v1

Phys. Rev. B 60, 344 (1999).

Physics

Condensed Matter

Disordered Systems and Neural Networks

22 pages, RevTeX + epsf, 4 figures

Scientific paper

10.1103/PhysRevB.60.344

We present some exact results for the effect of disorder on the critical properties of an anisotropic XY spin chain in a transverse field. The continuum limit of the corresponding fermion model is taken and in various cases results in a Dirac equation with a random mass. Exact analytic techniques can then be used to evaluate the density of states and the localization length. In the presence of disorder the ferromagnetic-paramagnetic or Ising transition of the model is in the same universality class as the random transverse field Ising model solved by Fisher using a real space renormalization group decimation technique (RSRGDT). If there is only randomness in the anisotropy of the magnetic exchange then the anisotropy transition (from a ferromagnet in the $x$ direction to a ferromagnet in the $y$ direction) is also in this universality class. However, if there is randomness in the isotropic part of the exchange or in the transverse field then in a non-zero transverse field the anisotropy transition is destroyed by the disorder. We show that in the Griffiths' phase near the Ising transition that the ground state energy has an essential singularity. The results obtained for the dynamical critical exponent, the typical correlation length, and the temperature dependence of the specific heat near the Ising transition agree with the results of the RSRGDT and numerical work.

Affiliated with

Also associated with

No associations

Rating

Effect of disorder on quantum phase transitions in anisotropic XY spin chains in a transverse field does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Effect of disorder on quantum phase transitions in anisotropic XY spin chains in a transverse field, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Effect of disorder on quantum phase transitions in anisotropic XY spin chains in a transverse field will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-583142