Programme

P.25 -- Poster, VCTP-44

Date: Tuesday, 30 July 2019

Time: 08:30 - 10:00

The formation of magnetization plateaus in the Sastry-Sutherland lattice with disorder.

Oanh Nguyen (1), Phong Nguyen (1), Long Dang (1), Cong Bach (2) and Giang Bach (2)

(1) University of Technology, Vietnam National University, Hanoi,Vietnam (2) Hanoi University of Science, Vietnam National University, Hanoi, Vietnam

We investigate disorder effects using Callen identities on the classical Ising model with anti-ferromagnetic (AF) spin couplings in the Sastry-Sutherland lattice. The simulation results indicate that the field-dependent magnetization curve of the Ising model consists of only one main plateau with a fractional value $m/m_s = 1/3$ (the saturation magnetization $m_s$) without disorder. In the inclusion of disorder, the fascinating sequence of the magnetization plateaus is surprisingly found with fractional values depending on the disorder probability of the AF exchange interaction between nearest neighbor and next nearest neighbor sites.Our results imply that dynamical mechanism driven by disorder induces multi-steps in the field- dependent magnetization curve which are experimentally observed in many compounds as SrCu$_2$(BO$_3$)$_2$ and rare-earth tetraborides RB$_4$ (R =Tm, Ho, Er).

Presenter: Bach Huong Giang