Self-homodyne tomography of a laser diode

Considerable interest is growing around self-homodyne techniques. Such techniques allow one to avoid non-unitary detection efficiencies due to inefficient mode matching of the local oscillator. Galatola et al (1991 Opt. Commun. 85 95) proposed one possible scheme of self-homodyne detection of a field with a strong coherent component involving the use of a Fabry-Perot cavity with a perfectly reflecting mirror. We extend the theory to arbitrary cavities, and we observe a remarkable agreement between the theory and the observed data. Using the same setup we performed a tomographic measure of the Wigner function of the field emitted by a laser diode.