IEICE Trans - Improvement of the Optical Gain in the Er-Doped Lithium Niobate Waveguide Optical Amplifiers

Improvement of the Optical Gain in the Er-Doped Lithium Niobate Waveguide Optical Amplifiers

Kiyoshi KISHIOKA
Tomonari KISHIMOTO
Kenta KUME

Publication
IEICE TRANSACTIONS on Electronics Vol.E88-C No.5 pp.1041-1052
Publication Date: 2005/05/01
Online ISSN:
DOI: 10.1093/ietele/e88-c.5.1041
Print ISSN: 0916-8516
Type of Manuscript: PAPER
Category: Optoelectronics
Keyword:
optical amplifier, Er-doped waveguide amplifier, LiNbO₃ waveguide,

Full Text: PDF(861.9KB)>>

Summary:
This paper describes improvement of the gain in the Er-doped lithium niobate waveguide optical amplifiers. A new configuration is proposed, which is loaded with a high-index cladding for the purpose of realizing a larger overlap between the guided light fields and doped Er ion-concentration. It is shown by theoretical simulations and also by experiments that the clad is advantageous to shifts of the light fields toward the substrate surface, and that the overlap between the light field and Er ion-concentration becomes large. Improved optical gains are measured for a fabricated device with a thin-TiO₂ clad in the LiNbO₃ substrate.