Waveguides sensitivity analysis for mid-infrared gas sensing

Raghi S. El Shamy; Mohamed A. Swillam; Diaa A. Khalil

doi:10.1117/12.2545068

25 February 2020 Waveguides sensitivity analysis for mid-infrared gas sensing

Raghi S. El Shamy, Mohamed A. Swillam, Diaa A. Khalil

Proceedings Volume 11283, Integrated Optics: Devices, Materials, and Technologies XXIV; 1128322 (2020) https://doi.org/10.1117/12.2545068
Event: SPIE OPTO, 2020, San Francisco, California, United States

Abstract

In this work we study various types of photonic waveguides for gas sensing in mid-infrared (MIR) region. MIR region which contains the absorption peaks of many gases is the most suitable region for gas detection. Operating near the absorption peak of the gas to be detected enhance the sensor performance significantly as both real and imaginary parts of the detected gas refractive index are maximized, which enhance the sensitivity and leads to lower detection limit. Here we focus on refractive index sensors that relies on the detection of the real part (n) of the refractive index. Refractive index sensors are strong candidates for integrated on chip sensors, where a small sample volume is needed. One of the main parameters in designing refractive index sensor is waveguide sensitivity which is defined as the ratio of the waveguide effective index change to the medium refractive index change, S_wg=Δn_eff/Δn_med. Thus rigorous sensitivity analysis using full-vectorial finite difference mode solver have been carried out to determine the waveguide sensitivity of such waveguides to gaseous medium. We use silicon on sapphire (SOS) platform to operate in the MIR region from 2μm to 6μm. For each structure we make sensitivity analysis once with undoped silicon and once with doped silicon to show how converting the same structure from dielectric to plasmonic will affect its performance as sensor. The dependence of the effective index, sensitivity and mode loss of each waveguide on the different waveguide dimensions was studied. Finally, a comparison between the proposed waveguides is provided.

Citation Download Citation

Raghi S. El Shamy, Mohamed A. Swillam, and Diaa A. Khalil "Waveguides sensitivity analysis for mid-infrared gas sensing", Proc. SPIE 11283, Integrated Optics: Devices, Materials, and Technologies XXIV, 1128322 (25 February 2020); https://doi.org/10.1117/12.2545068

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
9 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Waveguides

Silicon

Sensors

Refractive index

Plasmonics

Plasmonic waveguides

Waveguide modes

Show All Keywords

Keywords/Phrases

Search In:

Publication Years