Photonics integrated circuit optical amplifier

A photonics integrated circuit (PIC) chip comprising:

• a substrate formed of semiconductor material;
• first and second optical waveguides formed on the substrate, wherein each optical waveguide defines a path having first and second ends;
• a first optical isolator formed on the substrate in the path of the first optical waveguide to receive light input into the first end of the first optical waveguide, wherein the first optical isolator is operative for allowing the passage of the light input into the first end of the first optical waveguide and to avoid or prevent a reflection of the light back to the first end of the first optical waveguide after passage through the first optical isolator;
• a coupler formed on the substrate in the path of the first optical waveguide after the first optical isolator, wherein the coupler is operative for combining the light from the first optical isolator with light from a pump light source positioned off of the substrate and for outputting the combined light from the coupler via the second end of the first optical waveguide to an optical fiber positioned off of the substrate;
• and
• a second optical isolator formed on the substrate in the path of the second optical waveguide to receive the combined light input into the first end of the second optical waveguide from the optical fiber, wherein the second optical isolator is operative for allowing the passage of the combined light input into the first end of the second optical waveguide from the optical fiber and to avoid or prevent a reflection of the combined light back to the first end of the second optical waveguide after passage through the second optical isolator.