Numerical demonstration of wavelength-insensitive tuning characteristics of ladder-type tunable filter for a widely tunable laser diode

Seok Hwan Jeong, Shinji Matsuo, Takaaki Kakitsuka, Hiroyuki Suzuki, Yuzo Yoshikuni

Research output: Contribution to journalArticle


We propose a wavelength-insensitive tunable ladder-type interferometric filter having a novel configuration for use in a widely tunable laser diode. The spectral characteristics of the proposed device are numerically analyzed and compared with those of our previously reported device regarding transmittance and bandwidth. Wavelength-insensitive tuning and flat-topped filter spectra are obtained by optimizing device parameters. We also discuss the applicability of the proposed ladder filter to a widely tunable laser. The proposed tunable laser has a nearly constant threshold current density with tuning current injection. The oscillation frequency of the laser diode can be stabilized by introducing chirping into the ladder filter to obtain a single passband response. These high-performance spectral characteristics make the proposed device feasible for wavelength- division-multiplexing-based systems.

Original languageEnglish
Pages (from-to)4090-4096
Number of pages7
JournalJapanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers
Issue number5 A
Publication statusPublished - 2006 May 9



  • Integrated optics
  • MMI coupler
  • Tunable filter
  • Tunable laser
  • Waveguide device

ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy(all)

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