Physics – Condensed Matter – Materials Science
Scientific paper
2007-07-13
Physics
Condensed Matter
Materials Science
5 figures. Phys. Rev. B (accepted July 12, 2007)
Scientific paper
10.1103/PhysRevB.76.064407
We study the effect of antiferromagnetic interactions on the single spin-flip Glauber dynamics of two different one-dimensional (1D) Ising models with spin $\pm 1$. The first model is an Ising chain with antiferromagnetic exchange interaction limited to nearest neighbors and subject to an oscillating magnetic field. The system of master equations describing the time evolution of sublattice magnetizations can easily be solved within a linear field approximation and a long time limit. Resonant behavior of the magnetization as a function of temperature (stochastic resonance) is found, at low frequency, only when spins on opposite sublattices are uncompensated owing to different gyromagnetic factors (i.e., in the presence of a ferrimagnetic short range order). The second model is the axial next-nearest neighbor Ising (ANNNI) chain, where an antiferromagnetic exchange between next-nearest neighbors (nnn) is assumed to compete with a nearest-neighbor (nn) exchange interaction of either sign. The long time response of the model to a weak, oscillating magnetic field is investigated in the framework of a decoupling approximation for three-spin correlation functions, which is required to close the system of master equations. The calculation, within such an approximate theoretical scheme, of the dynamic critical exponent z, defined as ${1/\tau} \approx ({1/ {\xi}})^z$ (where \tau is the longest relaxation time and \xi is the correlation length of the chain), suggests that the T=0 single spin-flip Glauber dynamics of the ANNNI chain is in a different universality class than that of the unfrustrated Ising chain.
Pini Maria Gloria
Rettori Angelo
No associations
LandOfFree
Effect of antiferromagnetic exchange interactions on the Glauber dynamics of one-dimensional Ising models 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 antiferromagnetic exchange interactions on the Glauber dynamics of one-dimensional Ising models, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Effect of antiferromagnetic exchange interactions on the Glauber dynamics of one-dimensional Ising models will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-60258