Quantum noise in VCSELs

In this paper, we study in detail the intensity noise characteristics of vertical-cavity surface-emitting lasers (VCSELs). We demonstrate the possibility of generating intensity squeezed light with free-running or injection-locked VCSELs. Sub-shot noise operation results from very strong anticorrelations between the transverse modes. These anticorrelations have also been analysed through the transverse spatial distribution of the intensity noise. In the case of two transverse modes above threshold, our experimental results are found to be in good agreement with the predictions of a phenomenological model.