Technologies for a beam expansion and collimation for photonic integrated circuits

An apparatus comprising:

• a photonic integrated circuit (PIC) die comprising:
• one or more waveguides, wherein the one or more waveguides are disposed near a top surface of the PIC die;
• one or more flat mirrors disposed on a bottom surface of the PIC die, the bottom surface opposite the top surface;
• one or more curved mirrors;
• and
• one or more couplers, wherein individual couplers of the one or more couplers are to couple light from the one or more waveguides towards one of the one or more flat mirrors,
• wherein individual flat mirrors of the one or more flat mirrors are to reflect light from one of the one or more couplers towards one of the one or more curved mirrors,
• wherein the one or more curved mirrors are formed in a cavity defined in a substrate of the PIC die, wherein the one or more curved mirrors are a different material from the substrate.

An apparatus comprising:

• a photonic integrated circuit (PIC) die comprising:
• one or more waveguides, wherein the one or more waveguides are disposed near a top surface of the PIC die, wherein the one or more waveguides extend to a side surface of the PIC die;
• and
• one or more curved mirrors,
• wherein light from individual waveguides of the one or more waveguides is to exit the waveguide through the side surface towards one of the one or more curved mirrors,
• wherein the one or more curved mirrors reflect the light from individual waveguides of the one or more waveguides through a bottom surface of the PIC die opposite the top surface.

An apparatus comprising:

• a photonic integrated circuit (PIC) die comprising one or more waveguides;
• means for collimating light from the PIC die, wherein the means for collimating light from the PIC die is fixed in place relative to the PIC die,
• wherein the one or more waveguides are disposed near a top surface of the PIC die, wherein the one or more waveguides extend to a side surface of the PIC die, wherein the means for collimating light from the PIC die comprises one or more curved mirrors, wherein light from individual waveguides of the one or more waveguides is to exit the waveguide through the side surface towards one of the one or more curved mirrors,
• wherein a principal ray of light from individual waveguides of the one or more waveguides is to exit the side surface parallel to the top surface of the PIC die towards one of the one or more curved mirrors.