Properties of standing spin waves in a thin film of field-induced metamagnet with modified surface exchange interactions: I. Eigenvalue problem and stability conditions

Authors:

• Wojciech Rudziński,
• W. Maciejewski

Abstract

Properties of surface spin waves are studied in a thin film of the field-induced metamagnet which consists of ferromagnetically ordered layers parallel to the (001) plane, with intralayer ferromagnetic exchange coupling, interlayer antiferromagnetic exchange coupling as well as a strong three-ion anisotropy. A special Rutherford mathematical procedure for the description of the surface properties of finite crystal structures is generalized and applied to solve the eigenvalue problem for standing spin waves existing in the paramagnetic phase of the metamagnet at low temperatures. Also, by allowing the surface exchange parameters to deviate from the bulk values the stability conditions for the system are taken under theoretical discussion.