Scattering Metal Waveguide Based Speckle-Enhanced Prism Spectrometry


Cetindag S. K., Toy M. F., Ferhanoğlu O., Çivitci F.

JOURNAL OF LIGHTWAVE TECHNOLOGY, cilt.38, sa.7, ss.2022-2027, 2020 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 38 Sayı: 7
  • Basım Tarihi: 2020
  • Doi Numarası: 10.1109/jlt.2019.2959140
  • Dergi Adı: JOURNAL OF LIGHTWAVE TECHNOLOGY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, PASCAL, Aerospace Database, Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
  • Sayfa Sayıları: ss.2022-2027
  • İstanbul Teknik Üniversitesi Adresli: Evet

Özet

We present an optical efficiency improved speckle spectrometer where a scattering metal wave-guide is utilized along with a conventional prism spectrometer. We conducted extensive tests on 25 different scatterers, involving a variety of nanoparticle concentrations, scattering layer thicknesses, and wave-guide vs. non-guiding type scatterers. We observed 35 pm spectral resolution at 1.3% optical efficiency, which we could only achieve with similar to 0.01% optical efficiency using a conventional non-guiding scatterer. Thus our new implementation provides up to two orders of magnitude improvement in optical efficiency at the same spectral resolution, as opposed to scatterers that are not sandwiched between metal plates. The improvement in optical efficiency allows for rapid (similar to 5 mu sec exposure) acquisition of the spectrum with a conventional CMOS camera. Thanks to its excellent spectral resolution and diminished optical losses, the proposed spectrometer could be utilized in high frame-rate, real time spectrum reconstruction applications, such as Optical Coherence Tomography.