Multiple magnetization plateaus induced by farther neighbor interactions in an S=1 two-leg Heisenberg spin ladder

Abstract

We study the magnetization process of the S = 1 Heisenberg model on a two-leg ladder with further neighbor spin-exchange interaction. We consider the interaction that couples up to nextnearest neighbor rungs. We find an exactly solvable point at which the magnetization plateaus take the multiples of 1/6 and draw a general phase diagram for weaker next-nearest neighbor interaction using the density matrix renormalization group method. We observe a sizable parameter region where magnetization plateaus at multiples of 1/6 and 1/4 coexist.