The phase-locking of multiple spin-torque nano oscillators(STNOs) is considered the primary vehicle to achieve sufficient signal quality for applications. This book highlights the resonator's design and its need for feedback for phase locking of STNOs. STNOs can act as sources of tunable microwaves after being phase-locked together. External feedback from a coplanar waveguide placed above an STNO helps ensures coherent single domain oscillations. STNOs placed within magnonic crystal cavities also demonstrate coherent oscillations. Arrays of such cavities provide a route to scale power levels...

This book briefly looks at numerical modeling and micromagnetic simulation results of magnonic crystals, which are periodically modulated magnonic devices regarded as the magnetic counterpart of photonic crystals with spin waves acting as the information carrier. Since the wavelength of the spin wave is several orders of magnitude shorter than that of electromagnetic waves of the same frequency, magnonic crystals are promising candidates for miniaturization, especially in the fields of data storage and processing. The book begins by describing the dispersion relation of dipolar spin waves in...