Three-dimensional antiferromagnet Nd2BaNiO5 is the related substance of the Haldane system Y2BaNiO5. Although Nd2BaNiO5 has one-dimensional NiO6 chains, these chains were connected by Nd-Ni antiferromagnetic interactions and Nd2BaNiO5 undergoes antiferromagnetic order below TN = 48 K. In order to investigate the magnetic anisotropy of Nd2BaNiO5, aligned powder samples of Nd2BaNiO5 were prepared and were studied by the submillimeter wave ESR and highfield magnetization measurements. Although two magnetic transitions at 9.6 and 16.2 T were known by previous magnetization measurements using powder samples, the measurements using our aligned powder samples revealed that these transitions are metamagnetic transitions. Antiferromagnetic modes, which have antiferromagnetic gaps of 240 GHz and 1 THz, have been also observed by the submillimeter ESR measurements at 1.8 K. The origin of these modes is discussed.
|Number of pages
|Physica Status Solidi (B): Basic Research
|Published - 1999 Oct