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arXiv · 2001.09163

Highly-Chirped Bragg Gratings for Integrated Silica Spectrometers

James W. Field·Sam A. Berry·Rex H. S. Bannerman·Devin H. Smith·Corin B. E. Gawith·Peter G. R. Smith·James C. Gates
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Abstract

A blazed chirped Bragg grating in a planar silica waveguide device was used to create an integrated diffractive element for a spectrometer. The grating diffracts light from a waveguide and creates a wavelength dependent focus in a manner similar to a bulk diffraction grating spectrometer. An external imaging system is used to analyse the light, later device iterations plan to integrate detectors to make a fully integrated spectrometer. Devices were fabricated with grating period chirp rates in excess of 100nm/mm, achieving a focal length of 5.5mm. Correction of coma aberrations resulted in a device with a footprint of 20mm x 10mm, a peak FWHM resolution of 1.8nm, a typical FWHM resolution of 2.6nm and operating with a 160nm bandwidth centered at 1550nm.

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BibTeXRIS

James W. Field, Sam A. Berry, Rex H. S. Bannerman, Devin H. Smith, Corin B. E. Gawith, Peter G. R. Smith, James C. Gates. 2020-01-24. Highly-Chirped Bragg Gratings for Integrated Silica Spectrometers. https://doi.org/10.1364/oe.389211%2010.5258%2Fsoton%2Fd1356

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