Share Email Print

Proceedings Paper

Thin film lithium niobate optical modulators for THz frequency applications
Author(s): Seyfollah Toroghi; John Rollinson; Mona Hella; Ingrid Wilke; Payam Rabiei
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Thin film lithium niobate optical modulators allow modulation of optical signals up to several THz due to perfect phase matching between RF signal and optical signal that can be achieved using thin film devices. The platform uses a ridge waveguide fabricated by direct etching of lithium niobate thin film fabricated on silicon substrates. The lithium niobate thin film has been developed and optimized in our facility. Transmission spectrum of fabricated micro-ring resonators on this platform shows a linewidth of approximately 7 pm corresponding to a Q value of 2.2×105 and an optical waveguide loss of 2 dB/cm. A coupling loss of -5 dB per coupler is obtained using grating couplers. Measured fiber to fiber insertion loss of the device is -10 dB. The measured 3-dB optical bandwidth of the fiber to fiber optical coupler is 45 nm. A Mach-Zehnder modulator consisting of two MMIs and 6 mm long arms were designed and fabricated on X-cut thin film of lithium niobate. Measured Vπ of the device is 7.5 V at low frequencies (i.e. 10KHz) for a device with 7 μm gap between the electrodes. The measured half-wave voltage-length product, Vπ.L, is equal to ~4.5 High speed measurement results of the device response are presented. A THz electric field of 10kV/mHz0.5 is detected with a low dynamic range OSA and it is estimated that a THz electric field with a strength as low as ~100V/mHz0.5 is detectable by modulating the optical signal using these modulators.

Paper Details

Date Published: 2 March 2020
PDF: 7 pages
Proc. SPIE 11279, Terahertz, RF, Millimeter, and Submillimeter-Wave Technology and Applications XIII, 112791R (2 March 2020); doi: 10.1117/12.2546735
Show Author Affiliations
Seyfollah Toroghi, Partow Technologies LLC (United States)
John Rollinson, Rensselaer Polytechnic Institute (United States)
Mona Hella, Rensselaer Polytechnic Institute (United States)
Ingrid Wilke, Rensselaer Polytechnic Institute (United States)
Payam Rabiei, Partow Technologies LLC (United States)

Published in SPIE Proceedings Vol. 11279:
Terahertz, RF, Millimeter, and Submillimeter-Wave Technology and Applications XIII
Laurence P. Sadwick; Tianxin Yang, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?