Mössbauer Study on a Diluted Triangular Antiferromagnet LuFeMgO₄

Abstract

Mössbauer study of ⁵⁷Fe of a single crystal LuFeMgO₄, a diluted triangular antiferromagnet, reveals two kinds of spin behavior, a weakly frustrated and a strongly frustrated ones. One kind of spin aligns along the c-axis with antiferromagnetic correlation and contributes to an almost constant H_hf at temperatures below T_cusp (spin glass like transition temperature), while the other behaves like a Heisenberg spin in a triangular antiferromagnet rapidly fluctuating with 120° structure, and contributes to a slightly smaller and temperature dependent H_hf. This behavior is explained in relation to the magnetic properties.