ABSTRACT
This chapter shows that the main features of spin wave dispersion relation in homogeneous thin films. It introduces selected excerpts from the theory of spin waves especially important for spin wave propagation in magnonic crystals and presents the plane wave method (PWM) suitable for calculations of the magnonic band structure. The chapter explains basic properties of spin waves propagating in periodic structures and discusses the most interested features from the scientific and technological point of view. It describes the formation of the magnonic band structure and the opening of the magnonic band gap with simple model based on analysis of the dispersion relation of the homogeneous thin ferromagnetic films, supported also with numerical results from PWM. The chapter also describes the basic element of any magnonic device, it is the spin wave waveguide based on an antidot lattice.
