  We study the dynamics of molecular nanomagnets through a fully quantum
mechanical model describing high-spin and high-anisotropy magnetic molecules
subjected to a time-dependent magnetic field along the quantization axis, which
continuously inverts the population of spin states. Crystals of molecular
nanomagnets placed inside a resonant cavity interact with a quantized
electromagnetic field. Relaxation of excited states takes place by means of
spin-photon interaction, allowing stimulated emission of radiation and creating
a maser effect.
