Entangled photon pair sources are essential for applications such as quantum communication and metrology. Here we present a compact energy–time entangled photon pair source at telecom wavelengths realized through cascaded second harmonic generation and spontaneous parametric down conversion in a single periodically poled lithium niobate waveguide. We introduce and characterize methods to diminish the effects of Raman scattering, the principal being quasi-CW pumping. The quality of energy–time entanglement produced by the compact source is analyzed using two-photon interference and Franson interference, and visibilities as high as 93.9% ± 0.4% and 90.5% ± 0.6% are achieved, respectively.
|Number of pages||6|
|Journal||Journal of the Optical Society of America B: Optical Physics|
|Publication status||Published - 2021|