Evanescently coupled multimode spiral spectrometer
Abstract
We designed a high-resolution compact spectrometer based on an evanescently-coupled multimode spiral waveguide. Interference between the modes in the waveguide forms a wavelength-dependent speckle pattern which is used as a fingerprint to identify the input wavelength after calibration. Evanescent coupling between neighboring arms of the spiral results in a non-resonant broad-band enhancement of the spectral resolution. Experimentally, we demonstrated a resolution of 0.01 nm at a wavelength of 1520 nm using a 250 {\mu}m radius spiral structure. Spectra containing 40 independent spectral channels are recovered simultaneously and the operation bandwidth is significantly increased by applying compressive sensing to sparse spectra reconstruction.
Cite
@article{arxiv.1603.01612,
title = {Evanescently coupled multimode spiral spectrometer},
author = {Brandon Redding and Seng Fatt Liew and Yaron Bromberg and Raktim Sarma and Hui Cao},
journal= {arXiv preprint arXiv:1603.01612},
year = {2016}
}
Comments
10 pages, 7 figures, in submission