Induced photon statistics in three-level lasers

The statistical properties of three-level lasing are investigated theoretically. It is assumed that the three-level medium is coherently excited by another laser with an arbitrary photon statistics. It is proved that, under the specific conditions, the photon statistics of the three-level laser duplicate the photon statistics of the exciting laser. We call this phenomenon an induced photon statistics . We suggest to use this to analyze the statistical properties of a laser involved into a feedback process. Applying this laser for the coherent pump of a three-level laser, we can follow its photon statistics by means of direct following the three-level generation. In accordance with Ref. [1], we conclude that the feedback in itself is unable to generate the non-classical manifestation in the laser field.