Method for forming groove in hybrid optical device, and hybrid optical device

A hybrid optical device comprising:

• a quartz-based waveguide chip including a first waveguide comprising quartz-based glass as a main material;
• and
• a secondary nonlinear waveguide chip including a second waveguide comprising a secondary nonlinear optical material having a periodically poled structure;
• wherein a groove is disposed on a connection end surface of the quartz-based waveguide chip with the secondary nonlinear waveguide chip to divide a first region where light propagates through the first waveguide from a second region where light does not propagate;
• wherein the connection end surface of the quartz-based waveguide chip is bonded to a connection end surface of the secondary nonlinear waveguide chip with an adhesive provided in the second region;
• and
• wherein a marker extending in an in-chip plane direction from an end point of the groove extending in the in-chip plane direction from the connection end surface of the quartz-based waveguide chip is disposed in a core layer of the first waveguide of the quartz-based waveguide chip.

A method of manufacturing a groove in a hybrid optical device, the method comprising:

• forming a marker indicating a planned cutting line extending from a connection end surface of a quartz-based waveguide chip in an in-chip plane direction by processing a core layer of a waveguide of the quartz-based waveguide chip;
• aligning an irradiation position of laser light with a position of a starting point of the marker while quartz-based waveguide chip is placed on a stage;
• and
• manufacturing the groove on the connection end surface of the quartz-based waveguide chip so as to divide a first region where light propagates through the waveguide from a second region where the light does not propagate by moving the stage in an extending direction of the marker while irradiating the quartz-based waveguide chip with the laser light from an upper side of the quartz-based waveguide chip.