Novel Methods of Estimating Polarization Dependence in Semiconductor Optical Amplifiers Integrated with Spot-Size Convertors

Toshio ITO
Katsuaki MAGARI
Yasuo SHIBATA
Yoshihiro KAWAGUCHI
Yasuhiro KONDO
Yuichi TOHMORI
Yasuhiro SUZUKI

Publication
IEICE TRANSACTIONS on Electronics   Vol.E86-C    No.5    pp.831-837
Publication Date: 2003/05/01
Online ISSN: 
DOI: 
Print ISSN: 0916-8516
Type of Manuscript: PAPER
Category: Lasers, Quantum Electronics
Keyword: 
semiconductor optical amplifier,  polarization dependence,  gain ripple,  amplified spontaneous emission,  

Full Text: PDF(422.8KB)>>
Buy this Article


Summary: 
We propose a novel method of precisely measuring the polarization dependence of single pass gain (PDG) in a semiconductor optical amplifier integrated with spot-size convertors (SS-SOA). By averaging the signal gain of a SS-SOA over a wide wavelength range using the amplified spontaneous emission (ASE) of an erbium doped fiber (EDF), the PDG can be accurately estimated. This is because the influence of gain ripples on the measurement results are drastically reduced. We successfully evaluated the PDG of an angled-facet SS-SOA, even before the process of anti-reflection coating, within a small error of 0.5dB. The EDF-ASE technique is useful in sampling tests and selecting angled-facet SS-SOA chips from wafers. The polarization dependence of the coupling efficiency (PDCE) between a SS-SOA and optical fiber is also evaluated by measuring the photo-current of the active layer for TE and TM input signals. It is possible, therefore, to specify the polarization characteristics of the active region and spot-size converter region, which are indispensable parameters for the design of the SS-SOA.