Coupling between magnetic and thermodynamic properties in R Rh 2 Si 2 ( R = Dy, Ho)

Single crystals of DyRh 2 Si 2 and HoRh 2 Si 2 were investigated by thermal expansion and magnetostriction. The different types of magnetic order can clearly be seen in these measurements, particularly the canting of the moments away from the crystallographic c direction below about 12 K and the spin flip for magnetic field applied along the c direction. For HoRh 2 Si 2 , an additional transition just below T N is analyzed by means of the Grüneisen ratio and is likely caused by a change in the magnetic structure. Our results nicely corroborate findings from other magnetic and thermodynamic measurements on these materials and provide further evidence suggesting the formation of magnetic domains.