Resonant experiments in magnetism: superradiance and magnetic spectroscopy

We discuss the use of high-spin molecular clusters combined with microwave resonators to generate coherent microwave radiation and measure its frequency and power. The staircase demagnetization energy in molecular magnets may appear as coherent emission of microwave power forming geometry-dependent standing waves in the resonator. We observed that the equilibrium magnetization of these materials is strongly affected by the microwave radiation injected into the resonator and also studied the influence of selective microwave absorption on spin tunneling.