Gain control of semiconductor optical amplifier using a bandpass filter in a feedback loop

Khurram Karim Qureshi, Hwa Yaw Tam, Chao Lu, Ping Kong Alexander Wai

Research output: Journal article publicationJournal articleAcademic researchpeer-review

7 Citations (Scopus)


The authors present a simple configuration of a gainclamped semiconductor optical amplifier (GC-SOA) based on automatic intensity control of a feedback light generated by amplified spontaneous emission, using a narrowbandwidth thin-film-tunable filter. Experimental results show that the proposed amplifier has good gain clamping characteristics and the feedback light dramatically reduces steady and transient gain variations. The feedback light operates satisfactorily with the channel's add-drop frequency up to 20.9 kHz.We also examined the performance of the GC-SOA by employing the feedback light at different wavelengths.
Original languageEnglish
Pages (from-to)1401-1403
Number of pages3
JournalIEEE Photonics Technology Letters
Issue number18
Publication statusPublished - 15 Sep 2007


  • Optical gain control
  • Relaxation oscillations
  • Semiconductor optical amplifier (SOA)

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Electrical and Electronic Engineering

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