Patent ID: 9274274
Filing Date: 2016-03-01
CPC Classification: G02B,G02F

Claim Text:
1. A method to configure a photonic chip based on periodical poling and waveguides circuits in ferroelectric crystals, said method is based on the integration of waveguide circuits, periodical poling and an electrooptic modulator (EOM), comprising: using the waveguide circuits to guide the photons and perform linear operations including beam-splitting, filtering on photons; using the periodical poling to enable efficient spontaneous parametric down conversion (SPDC) and generation of a pair of entangled photons; controlling phase of the photons dynamically using the EOM; coupling the chip first with a classical pump beam and then splitting into two pump beams by a waveguide Y-junction; and using the periodical poling region to generate the pair of entangled photons from either of two pump beams; distributing the pair of entangled photos subsequently using a directional waveguide coupler, performing quantum interference, and resulting different types of path-entangled states by controlling the voltage of EOM insides the chip; and making the waveguide circuits and domain modulation in certain regions on homogeneous ferroelectric substrate including lithium niobate (LN), wherein the-whole chip is divided into three regions, including: