We determined the crystal structure of Ba2CoSi2O6Cl2, which was synthesized in this work, and investigated its quantum magnetic properties using single crystals. This compound should be described as a two-dimensionally coupled spin-1/2 XY-like spin dimer system. Ba2CoSi2O6Cl2 exhibits a stepwise magnetization process with a plateau at half of the saturation magnetization, irrespective of the field direction, although all the Co2+ sites are equivalent. This indicates that spin triplets are localized owing to the almost perfect frustration of interdimer exchange interactions. Thus, the spin states for the zero and 1/2 magnetization-plateau states are almost exactly given by the simple product of singlet dimers and the alternate product of singlet and triplet dimers, respectively.
@article{arxiv.1404.2033,
title = {Almost Perfect Frustration in the Dimer Magnet Ba$_2$CoSi$_2$O$_6$Cl$_2$},
author = {Hidekazu Tanaka and Nobuyuki Kurita and Makiko Okada and Eiji Kunihiro and Yutaka Shirata and Kotaro Fujii and Hidehiro Uekusa and Akira Matsuo and Koichi Kindo and Hiroyuki Nojiri},
journal= {arXiv preprint arXiv:1404.2033},
year = {2014}
}
Comments
8 pages, 8 figures, published in J. Phys. Soc. Jpn. http://dx.doi.org/10.7566/JPSJ.83.103701