0 Weak ferromagnetism of quasi - one - dimensional S = 1 / 2 antiferromagnet BaCu
نویسندگان
چکیده
Weak ferromagnetism of quasi-one-dimensional S = 1/2 antiferromagnet BaCu 2 Ge 2 O 7 is studied by the magnetization measurement. The spontaneous magnetization appears along the b axis below 8.8 K. The local symmetry between the intra-chain nearest neighbor spins allows the presence of Dzyaloshinskii-Moriya interaction, and the only possible spatial configuration of the weak ferromagnetic moment per spin uniquely determines the sign of the inter-chain interaction. A weak a-axis magnetic field can change the direction of the magnetization to the a-axis direction, which shows that the spin chain forms a weakly coupled weak-ferromagnetic chain system.
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