Figure 6: Spontaneous parametric down conversion (SPDC) source and coincidence counting set-up.
From: Quantum interference between transverse spatial waveguide modes
The photon pair source is coupled to the chip using lensed fibres and coupled to the coincidence counting setup using a fibre array. The polarization is filtered using a series of a half-wave plate (HWP), quarter-wave plate (QWP) and polarizing beamsplitter (PBS).
