Selective light modulation in waveguide grating using phase change materials  (Conference Presentation)

Mohsen Jafari; L. Jay Guo; Mina Rais-Zadeh

doi:10.1117/12.2511198

4 March 2019 Selective light modulation in waveguide grating using phase change materials (Conference Presentation)

Mohsen Jafari, L. Jay Guo, Mina Rais-Zadeh

Proceedings Volume 10921, Integrated Optics: Devices, Materials, and Technologies XXIII; 109210L (2019) https://doi.org/10.1117/12.2511198
Event: SPIE OPTO, 2019, San Francisco, California, United States

Abstract

This paper reports for the first time a high-contrast, low-power reflective color filter employing a phase change material in a waveguide grating with different periods. Refractive index modulation is produced by crystallographic phase transition of Germanium Telluride (GeTe) using an external stimulus, such as heat. Nanostrips of GeTe are used due to their reliable, fast, and reversible phase transitions. These thin nanostrips reduce the total light absorption and yield a vivid, bright reflected color. Moreover, a buried optical waveguide consisting of a silicon nitride (Si₃N₄) core, which was grown between two layers of silicon dioxide (SiO₂) cladding, is placed under these gratings to enhance the color contrast. The waveguide resonance is enhanced using a bottom palladium reflector and GeTe gratings above with different periods. Selective absorption within visible-NIR region that depend on the period of the grating and the phase of the GeTe is introduced within these devices for the first time. A unique anti-reflective coating was also re-introduced to suppress the surface reflection, thus enhancing the color contrast. Vivid reflected red and green colors have been shown for a device with active area of 400 μm². These colors were electrically transitioned to blue and yellow, respectively, for several cycles. We further report that GeTe nanostrips with different cross-sectional areas demonstrate different phase transition behaviors. Thus, several colors were achieved within the same area of the device employing GeTe nanostrips with different periods.

Conference Presentation

Citation Download Citation

Mohsen Jafari, L. Jay Guo, and Mina Rais-Zadeh "Selective light modulation in waveguide grating using phase change materials (Conference Presentation)", Proc. SPIE 10921, Integrated Optics: Devices, Materials, and Technologies XXIII, 109210L (4 March 2019); https://doi.org/10.1117/12.2511198

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
PRESENTATION

WATCH
PRESENTATION SAVE TO MY LIBRARY

GET CITATION

KEYWORDS

Phase shift keying

Waveguides

Ferroelectric materials

Modulation

Resonance enhancement

Absorption

Crystals

Show All Keywords

Keywords/Phrases

Search In:

Publication Years