Probing the stability of Shastry Sutherland lattice in Er₂Pd₂Sn and Er₂Pd₂In

The group of 2:2:1 compound crystalizing in the Mo₂FeB₂ structure type, more commonly known as R₂T₂X intermetallic (R = rare earth, T = transition metal, X =main group), have been reinvestigated recently owing to the spin liquid state in the underlying Shastry-Sutherland lattice (SSL) formed by the R [1, 2]. Our motivation in investigating this compound is to explore the interplay of frustration and quantum criticality. For this study we have selected less-investigated Er₂Pd₂In and Er₂Pd₂Sn. X-ray powder diffraction studies and subsequent Rietveld refinements confirmed that the compounds were phase-pure and crystallized in the tetragonal Mo₂FeB₂ structure. Both the compounds obeyed Curie-Weiss law in the paramagnetic regime, as judged from magnetic susceptibility data, which indicated anti-ferromagnetism. Specific heat data on both the compounds revealed a double peak indicating complex magnetic structure and phase transitions. We will present a detailed analysis of the magnetization and specific heat on both Er₂Pd₂(Sn/In). This motivated our current neutron diffraction experiment to determine the magnetic structure of these SSL compounds to probe for novel magnetic phases.