Separation of energy scales in the kagome antiferromagnet TmAgGe: a   magnetic-field-orientation study up to 55 T
  TmAgGe is an antiferromagnet in which the spins are confined to distorted kagome-like planes at low temperatures. We report angle-dependent measurements of the magnetization $M$ in fields of up to 55 T that show that there are two distinct and separate energy scales present in TmAgGe, each responsible for a set of step-like metamagnetic transitions; weak exchange interactions and strong crystalline electric field (CEF) interactions. Simulations of $M$ using a three-dimensional, free-energy minimization technique allow us to specify for the first time the physical origin of the metamagnetic transitions in low, in-plane fields. We also show that the transitions observed with the field perpendicular to the kagome planes are associated with the CEF-split multiplet of Tm. 
P. A. Goddard, J. Singleton, A. L. Lima-Sharma, E. Morosan, S. J.   Blundell, S. L. Bud'ko and P. C. Canfield