DEVICE COMPRISING PLANAR OPTICAL WAVEGUIDE AMPLIFIER

PROBLEM TO BE SOLVED: To provide a technology by which a POWA(planar optical waveguide amplifier) is coupled to a waveguide at low loss, to provide a device comprising the POWA connected to the waveguide, and to provide a method for manufacturing such a device. SOLUTION: The planar optical waveguide amplifier comprises a first planar optical waveguide 11 and a second planar optical waveguide 12 contacting to the first planar optical waveguide. The second planar waveguide comprises a planar waveguide doped with a rare earth element, and a first tapered part 13 which connects the electromagnetic radiation of at least one specified wavelength coming from the first planar optical waveguide to the planar waveguide doped with a rare earth element.