Observation of inversionless amplification in Sm vapour and related experiments

Abstract
An experiment is presented which demonstrates 'amplification without inversion' (AWI) and 'inversion without amplification' of a picosecond pulse in a generalized lambda-type system. The phenomena are based on Zeeman coherence in the J=1-level of the ground state multiplet in samarium, induced by a picosecond pulse train. The experiment and its relation to other AWI proposals and to previous experiments in atomic spectroscopy are discussed in detail.