著者
Iio Katsunori Sakatani Mitsuo Nagata Kazukiyo
出版者
一般社団法人日本物理学会
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.45, no.5, pp.1567-1574, 1978-11-15
被引用文献数
17

By measuring optical birefringences the behaviour of short-range order has beenstudied on quadratic-layer quasi-Heisenberg antiferromagnets : K.NiF., Rb.NiF.,Ba.NiF, and K.CoF.. An explicit form of the spin-dependent birefringence forthese systems is given, which is proportional to the nearest-neighbouring cor-relation functions<.SjS l >. It is shown that with increasing Ising-like characterthe high tempet'ature persistence of<S7,5Z>is rc:duced. In the case of K2C0F.,where the Ising-like anisotropy is comparable to the isotropic exchange field,a symmetric and logarithmic anomaly in the behaviour of<,SjS,) has beenobserved for 17' -7Nl/7'N<7.5'l0 " afound the Neel point.