Magnetic field-induced ordering in SrDy2O4.

Heat capacity measurements were used to investigate the magnetic ordering processes in single-crystal samples of SrDy2O4 in a magnetic field applied along the [010] and [001] directions. In zero field this compound appears to be magnetically disordered down to at least 0.39 K. A magnetic field applied along the [010] direction induces a very sharp transition at 20 kOe, seen as a strong peak in the heat capacity versus field, C(H) curves, while for H // [001], the magnetization process is accompanied by the development of only broad features in the C(H) curves. The process of field-induced ordering in SrDy2O4 appears to be rather remarkable even in the context of the unusual phase transitions observed in other geometrically frustrated magnetic systems consisting of hexagons and triangles.