Regular Article

Magnetization plateaus and phase diagrams of the extended Ising model on the Shastry-Sutherland lattice: effects of long-range interactions

Institute of Experimental Physics, Slovak Academy of Sciences, Watsonova 47, 040 01 Košice, Slovakia

^a e-mail: farky@saske.sk

Received: 21 June 2018
Received in final form: 21 November 2018
Published online: 11 February 2019

Abstract

Magnetization plateaus and phase diagrams of the extended Ising model on the Shastry-Sutherland lattice with the first (J₁), second (J₂), third (J₃) fourth (J₄) and fifth (J₅) nearest-neighbour spin couplings are studied by the classical Monte Carlo method. It is shown that switching on J₄ and J₅ interactions (in addition to usually considered J₁, J₂ and J₃ interactions) changes significantly the picture of magnetization processes found for J₄ = J₅ = 0 and leads to stabilization of new macroscopic magnetic phases (plateaus) with fractional magnetization. In particular, it is found that combined effects of J₄ and J₅ interactions generate the following sequence of plateaus with the fractional magnetization: m∕m_s = 1/9, 1/6, 2/9, 1/3, 4/9, 1/2, 5/9 and 2/3. Tuning the values of J₄ and J₅ parameters, the model can describe the appearance of the individual plateaus on the magnetization curves of some rare-earth tetraborides, as well as the partial sequence of magnetization plateaus, consisting of two, three and even more right plateaus.