On-chip Er-doped Ta₂O₅ waveguide amplifiers with a high internal net gain

Area of Science:

• Materials Science
• Optoelectronics
• Photonics

Background:

• Optical amplifiers are crucial components in modern communication systems.
• Tantalum pentoxide (Ta₂O₅) is explored as a potential host material for optical waveguides.
• Erbium (Er³⁺) doping is a common method for achieving optical gain in the telecommunication C-band.

Purpose of the Study:

• To design and fabricate a double-layered Er³⁺:Ta₂O₅ waveguide.
• To investigate the optical amplification performance of the fabricated waveguide in the C band.
• To evaluate the potential of Ta₂O₅ as a host material for waveguide amplifiers.

Main Methods:

• Fabrication of a double-layered Er³⁺:Ta₂O₅ waveguide structure.
• Experimental investigation of optical amplification using a 980 nm pump laser.
• Measurement of pump laser threshold, internal net gain, and gain dependence on signal input power.

Main Results:

• The pump laser threshold for zero gain at 1533 nm was determined to be 2.5 mW.
• An internal net gain of approximately 4.63 dB/cm was achieved at a pump power of 36.1 mW and signal input power of -30.0 dBm.
• A maximum internal net gain of 10.58 dB/cm was obtained at a signal input power of approximately -47.1 dBm.

Conclusions:

• The fabricated Er³⁺:Ta₂O₅ waveguide exhibits significant optical amplification capabilities in the C band.
• Tantalum pentoxide (Ta₂O₅) demonstrates strong potential as a host material for developing efficient optical waveguide amplifiers.
• The results support the advancement of integrated optical devices for telecommunications.