LAUSR

We present a simple model for a description of magnetization processes in metallic rare-earth tetraborides. It is based on the two-dimensional Ising model, in which two spins on the Shastry–Sutherland lattice interact via the long-range RKKY interaction mediated by conduction electrons. The model is solved by a combination of the standard Metropolis algorithm and the parallel tempering method and it yields the rich spectrum of magnetic solutions (magnetization plateaus), depending on the value of the Fermi momentum kF and the external magnetic field h. In particular, we have found the following set of individual magnetization plateaus with fractional magnetization m/ms = 1/12, 1/6, 1/4, 1/3, 3/8, 5/12, 1/2, 7/12, 2/3, which for different values of kF , form various sequences of plateaus, changing from very complex ones, appearing near the points kF = 2π/1.243 to very simple ones appearing away from this point. The importance of these results for a description of real rare-earth tetraborides is discussed.