Photonic integrated circuit for amplifying optical signals

A silicon photonic device, comprising:

• a first waveguide;
• and
• a photonic integrated circuit (PIC) coupled to the first waveguide, wherein the PIC comprises:
• a first mode field adapter (MFA) and a second MFA that are on a facet of the PIC, wherein
• one of the first MFA or the second MFA is configured to:
• output a first optical signal that is an amplified version of a second optical signal;
• and
• provide the first optical signal to the first waveguide, and
• the second optical signal is one of generated in the PIC or received by the PIC;
• a second waveguide that extends between the first MFA and the second MFA, wherein
• the second optical signal propagates through the second waveguide,
• the second waveguide is divided into a first waveguide arm, a second waveguide arm, and a bend portion,
• the bend portion joins the first waveguide arm and the second waveguide arm,
• the first waveguide arm integrates with the first MFA,
• a portion of the first waveguide arm is tilted at an angle,
• the second waveguide arm integrates with the second MFA,
• a portion of the second waveguide arm is tilted at the angle,
• each of the portion of the first waveguide arm and the portion of the second waveguide arm is opposite to the bend portion,
• the second waveguide is configured to amplify the second optical signal based on a current injected in the PIC,
• each MFA of the first MFA and the second MFA comprises:
• a third waveguide configured to one of:
• receive the second optical signal;
• or
• output the first optical signal;
• a tapered active waveguide core that extends between the third waveguide and the second waveguide, wherein the tapered active waveguide core enables one of:
• propagation of the second optical signal from the third waveguide to the first wavequide arm, or
• propagation of the first optical signal from the second wavequide arm to the third waveguide;
• and
• a fourth waveguide below the third waveguide, and
• the third waveguide is further configured to one of receive the second optical signal via the fourth waveguide, or output the first optical signal via the fourth waveguide;
• a first waveguide structure;
• a second waveguide structure;
• a third waveguide structure;
• a first plurality of contact pads above the first waveguide structure;
• a second plurality of contact pads above the second waveguide structure;
• and
• a third plurality of contact pads above the second waveguide structure, wherein
• the first waveguide arm is between the first plurality of contact pads and the second plurality of contact pads,
• the second waveguide arm is between the first plurality of contact pads and the third plurality of contact pads, and
• the current is injected in the PIC via each of the first plurality of contact pads, the second plurality of contact pads, and the third plurality of contact pads.