AlInGaAs Multiple Quantum Well-Integrated Device with Multifunction Light Emission/Detection and Electro-Optic Modulation in the Near-Infrared Range

High-performance thin-film lithium niobate electro-optic modulator based on etching slot and ultrathin silicon film

An electro-optic modulator (EOM) is an indispensable component to connect the electric and optical fields. Here, we propose a high-performance, thin-film lithium niobate-based EOM, where the modulation waveguide is formed by an etching slot on the lithium niobate film and the deposit of an ultrathin silicon film in the slot region. Therefore, a small mode size and high mode energy can be simultaneously achieved in the LN region with a high EO coefficient, which will be beneficial to increase the EO overlap and gradually decrease in the mode size. Further, we employed a waveguide structure to construct a typical Mach-Zehnder interference-type EOM. According to the requirements of high-speed traveling wave modulation, we conduct the index matching, impedance matching, and low-loss operation. From the results, the key half-wave voltage length product and 3 dB modulation bandwidth are, respectively, 1.45 V cm and 119 GHz in a modulation length of 4 mm. Moreover, a larger 3 dB bandwidth also can be achieved by shortening the modulation length. Therefore, we believe the proposed waveguide structure and EOM will provide new ways to enhance the performance of LNOI-based EOMs.

AlInGaAs MQW Transceiver with Electro-optic Modulation Characteristics for Free-Space Optical Communication and Sensing

Integrated transceivers with electro-optic modulation characteristics are valuable for free-space optical communications and sensing. We propose an AlInGaAs multiple quantum well (MQW) transceiver with electro-optic modulation characteristics over a broad spectral range. Two identical AlInGaAs MQW diodes on a single wafer are used to transmit and receive optical signals and provide obvious electro-optic modulation for broad-spectrum light. The photocurrent modulation ratio reaches 13.9 and 11.3 for white light and 1550 nm infrared light, respectively, with varying bias voltages. The transceiver can identify environmental changes and forward electrical signals with different frequencies in the form of superimposed optical signals.