  We demonstrate a method to generate entangled photons with controlled spatial
shape by parametric down conversion (PDC) in a 2D nonlinear crystal. A compact
and novel crystal source was designed and fabricated, generating directly path
entangled photons without the use of additional beam-splitters. This crystal
supports two PDC processes, emitting biphotons into two beamlike modes
simultaneously. Two coherent path entangled amplitudes of biphotons were
created and their interference observed. Our method enables the generation of
entangled photons with controlled spatial, spectral and polarization
properties.
