Home Optical Lab

This is my home optical lab. I've inherited almost all the components from a POC project I was doing for my company and then created the home lab having also bought some extra stuff on my own. It's not that impressive in general: few waveplates; beamsplitters, mirrors, filters, AOM's, HeNe and diode lasers, etc. but it did become special during the Covid lockdown. It previously resulted in an interesting formalism for 4 by 4 beamsplitter matrix (pre-print is peer-reviewed). It predicts photon coalescence not only in spatial modes but in polarization as well. The setup that is now on the picture is built to test it. Laser beam is attenuated by set of cross polarizers to get close to non-classical light statistics. It's followed by acousto-optic modulator having several diffraction orders with +1 and -1 treated as correlated ones to resemble the original HOM experiment with nonlinear emission of two down-converted photons. The challenging part is to get the pathlengths from AOM to recombining beamsplitter equal, so 4th order correlation can be observed (just as required by the original HOM experiment). The output legs have polarizing beamsplitters, so 4 beams are produced and shone upon the target plate. The CCD camera above provides back-scattered photon counts via LabView code on the PC. If perfect pathlengths matching is achieved there should be only 2 dots visible, i.e. coalescent in spatial and polarization modes.

—Artem Kryvobok, FLIR Systems, U.S.A.

01 Dec 2020