Phs. Ribeiro et al., CONTROLLING THE DEGREE OF VISIBILITY OF YOUNGS FRINGES WITH PHOTON COINCIDENCE MEASUREMENTS, Physical review. A, 49(5), 1994, pp. 4176-4179
Is it possible to detect the interference from an extended incoherent
source with Young's slits when the source-slits distance is such that
all dimensions of the coherence area of the incident light beam are sm
aller than the distance between the slits? We have experimentally demo
nstrated that, under the above conditions, interference fringes can be
obtained with a controlled degree of visibility by means of coinciden
ce measurements between conjugated beams of the down-conversion lumine
scence.