ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
There is considerable theoretical interest in triangular and stacked triangular lattice antiferromagnets, particularly as regards their phase transitions and the nature of the ground state of quantum systems with spin S=1/2. There are, however, no good experimental representatives of the S=1/2 triangular lattice antiferromagnet, and indeed there are few good representatives of those with higher spin. Given the diversity of theoretical problems associated with these systems there is a clear need to find appropriate new model materials. We report the discovery of a versatile new series of triangular lattice magnets, the anhydrous alums of general formula AM(SO4)2, with A=alkali metal, M=Ti,V,Cr,Fe. In these materials the magnetic M ions occupy a regular or very slightly distorted triangular lattice in well-separated layers. All show magnetic ordering effects in the range 2–10 K, the near-neighbor exchange being antiferromagnetic for Ti, V, and Fe and ferromagnetic for Cr. The Ti materials, which we have made for the first time, have S=1/2, and may prove to be the best examples of the S=1/2 triangular lattice antiferromagnet yet discovered. In general, our ability to control the spin value, spin anisotropy, and exchange anisotropy makes the anhydrous alums a potentially useful series for the investigation of a variety of physical problems. © 1996 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.362054
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