Anomalous evolution of the magnetocaloric effect in dilute triangular Ising antiferromagnets Tb1–xYx(HCO2)3

Falsaperna M, Bulled JM, Stenning GBG, Goodwin A, Saines PJ

We investigate the effects of diamagnetic doping in the solid-solution series Tb1−xYx(HCO2)3, in which the parent Tb(HCO2)3 phase has previously been shown to host a combination of frustrated and quasi-one-dimensional (quasi-1D) physics, giving rise to a triangular Ising antiferromagnetic ground state that lacks long range 3D order. Heat capacity measurements show three key features: (i) a low temperature Schottky anomaly is observed, which is constant as a function of x; (ii) the transition temperature and associated entropy change are both surprisingly robust to diamagnetic doping; and (iii) an additional contribution at T