Inversionless radiation amplification by ions having certain velocities in a magnetic field

It is shown that the imposition of external magnetic field on a gas of ionised particles may give rise to inversionless radiation amplification by the ions having certain velocities, which is due to their Larmor rotation. In this case, the majority of ions may reside in the ground state. The integrated absorption coefficient remains positive due to an increase in the radiation absorption by the other half of ions.