Dynamics Near Multicritical Points

Vladimir V. Prudnikov, G. B. Teǐtel'Baum

Amnon Aharony A

Amnon Aharony A

Marshall Luban, Richard M. Hornreich, Shtrikman

Richard M. Hornreich, Marshall Luban, S. Shtrikman

Shunji Moriya, K. Nomura

We propose a new method to numerically calculate transition points that belongs to 2D Ising universality class for quantum spin models.Generally, near the multicritical point, in conventional methods, a finite size correction becomes very large.To suppress the effect of the multicritical point, we use a z-axis twisted boundary condition and a y-axis twisted boundary condition.We apply our method to an S = 1 2 bond-alternating XXZ model.The multicritical point of this model has a BKT transition, where the correlation length diverges singularly.However, with our method, the convergence of calculation is highly improved, thus we can calculate the transition point even near the multicritical point.