Abstract
Photonic-integrated circuits (PICs) using ferroelectric materials are expected to be used in many applications because of its unique optical properties such as large electro-optic coefficients. In this study, a novel PIC based on a ferroelectric thin-film platform was designed and fabricated, where high-speed optical modulator, spot-size converters (SSCs), and a variable optical attenuator (VOA) were successfully integrated. A ferroelectric lanthanum-modified lead zirconate titanate (PLZT) thin film was epitaxially-grown by using a modified sol-gel method, and it exhibits large electro-optic coefficients (>120 pm/V) and low propagation loss (1.1 dB/cm). The optical modulator, a Mach-Zehnder type, exhibited a half-wave voltage (Vπ) of 6.0 V (VπL = 4.5 Vcm) and optical modulation up to 56 Gb/s. Also, the VOA (with attenuation range of more than 26 dB) was successfully integrated with the modulator. As a result, it is concluded that the developed ferroelectric platform can pave the way for photonic integration.
Highlights
Photonic-integrated circuits (PICs) using ferroelectric materials are expected to be used in many applications because of its unique optical properties such as large electro-optic coefficients
Input light generated by the laser diode (LD) is fed into the PLZT PIC and converted into non-return-to-zero (NRZ) high-speed optical signals by the optical modulator
For sensitivity tests of optical transceivers, optical power can be varied by the variable optical attenuator (VOA), and the power level of each signal can be monitored by the monitor PDs
Summary
Photonic-integrated circuits (PICs) using ferroelectric materials are expected to be used in many applications because of its unique optical properties such as large electro-optic coefficients. A novel PIC based on a ferroelectric thin-film platform was designed and fabricated, where highspeed optical modulator, spot-size converters (SSCs), and a variable optical attenuator (VOA) were successfully integrated. LN modulators typically employ weakly guiding waveguides fabricated by titanium diffusion, so their resulting size is several centimeters in length Their optical performance is sometimes deteriorated by a photorefractive effect during input of high-power optical signals. SOH modulators can be expected to achieve both high-speed optical modulation and photonic integration because of their large EO coefficient, their fabrication process needs to be further improved to reduce optical propagation loss of the highly confined slot waveguides
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
