DYNAMICS OF A MONOVELOCITY-ATOMIC-BEAM MASER FRAMED IN A SEMICLASSICAL MODEL

For a sufficient number of atoms and in the framework of a semiclassical two-level model the beam maser exhibits multiple, steady-state intensity branches. We investigate the field evolution along the specific branches of the system and discuss the physics of transitions between these branches. We find that branch hopping, hysteresis, and bistability are present under high-cavity-Q conditions and that relaxation frequency shifts occur at crucial values of the excitation when these branch transitions take place. Spectra, phase-space portraits, and temporal behavior of the output field are analyzed. Dimensional analysis reveals the fractal dimension of a chaotic trajectory. Experimental conditions for the beam maser are examined.