A5101993720- Photonic and Optical Devices
- Photorefractive and Nonlinear Optics
- Advanced Fiber Laser Technologies
- Magneto-Optical Properties and Applications
- Semiconductor Lasers and Optical Devices
- Electric Power System Optimization
- Power Systems and Renewable Energy
- Wind Turbine Control Systems
- Network Security and Intrusion Detection
- Optical Coatings and Gratings
- Infrastructure Resilience and Vulnerability Analysis
- Advanced Photonic Communication Systems
- Acoustic Wave Resonator Technologies
- Smart Grid Security and Resilience
Tsinghua University
2018-2024
Tsinghua–Berkeley Shenzhen Institute
2024
A novel thin-film lithium niobate (TFLN) electro-optic modulator is proposed and demonstrated. LiNbO3-silica hybrid waveguide adopted to maintain low optical loss for an electrode spacing as narrow 3 µm, resulting in a half-wave-voltage length product of only 1.7 V·cm. Capacitively loaded traveling-wave electrodes are employed reduce the microwave loss, while quartz substrate used place silicon achieve velocity matching. The fabricated TFLN with 5-mm-long modulation region exhibits half-wave...
Compact thin-film lithium niobate (TFLN) modulators with low half-wave voltage <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{V}_{\pi }$ </tex-math></inline-formula> are highly desirable for many applications. In particular, }~\sim ~1$ V would allow direct driving by CMOS circuits, but they normally require a long modulation length of several centimeters. Folded TFLN exhibit reduced together small...
A thin film lithium niobate (TFLN) electro-optic modulator based on a partially removed benzocyclobutene (BCB) bonding layer is proposed for sub-terahertz bandwidth. Low-loss microwave transmission realized by periodic capacitively loaded travelling-wave electrodes (CL-TWEs) with an undercut structure, and the air-filled region beneath arms adjusted to secure impedance velocity matching. low half-wave voltage length product of 1.2 V·cm can be achieved 2-µm-gap electrodes, while 3-dB...
Traveling-wave electro-optic (E-O) modulators based on thin-film lithium niobate (TFLN) have attracted much attention recently, as low half-wave voltage ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{V}_{\pi }$ </tex-math></inline-formula> ) and wide modulation bandwidth can be realized with a small footprint. A flat E-O response of the modulator relies microwave loss, perfect velocity match...
We propose a thin film lithium niobate modulator based on photonic crystal waveguide and slow wave electrodes. Simulations predict low half-wave voltage of 2 V as well an ultrawide-bandwidth over 200 GHz.
The widely used intelligent measuring equipment not only makes the operation of AC/DC hybrid transmission system more safe and reliable, but also inevitably brings new problems challenges such as threats hidden dangers cyber attacks. Given this, how to effectively comprehensively assess inherent vulnerabilities systems under coordinated physical-cyber attacks is critical significance. In this paper, a three-stage attack defense risk assessment framework based on dynamic game theory proposed....
Novel electro-optic modulators are fabricated based on LiNbO 3 -silica hybrid waveguide and capacitively-loaded electrodes. Record-low half-wave-voltage length product of 1.7 V·cm modulation bandwidth > 67 GHz demonstrated.
Meandered thin-film lithium niobate modulators with capacitively loaded travelling-wave electrodes are demonstrated. Interdigitated T-rails employed for reversed electric field, resulting in 1.08 V half-wave voltage and 3-dB bandwidth beyond 50 GHz 8-mm-long devices.
A novel thin-film lithium niobate (TFLN) electro-optic modulator with low half-wave-voltage length product is designed and fabricated. LiNbO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> -Silica hybrid waveguide adopted to achieve an electrode gap as narrow 3 μm without deterioration of optical transmission, resulting in a high electric field loading efficiency product. Furthermore, periodically loaded T-rail electrodes are employed...
A novel thin film lithium niobate modulator with metal-filled photonic crystal is proposed to greatly enhance the electro-optical interaction. Half-wave-voltage of 2 V and bandwidth over 200 GHz can be realized a 500-μm-long device.
High-speed thin-film lithium niobate modulator with on-chip terminal resistor is demonstrated. The 6-mm-long equipped capacitive-loaded travelling-wave electrodes, and exhibits a half-wave-voltage of 2.7 V 3-dB modulation bandwidth exceeding 50 GHz.
A novel thin film lithium niobate modulator is proposed. Half-wave voltage of 1.9 V and bandwidth 300 GHz can be obtained, together with buried edge couplers exhibiting low coupling loss 0.27 dB/facet.
Optical phased arrays (OPAs) are widely used in many applications to realize high-speed optical beam scanning. At present OPAs often suffer from limited scanning range. Here we propose a circular array (COPA) based on silicon photonics platform. According our simulations, by positioning the OPA units circle and adopting specific phase distribution, COPA can 360° constant amplitude In addition, design of disk grating coupler, which is key device COPA, presented. The believed have great...
A thin-film lithium niobate modulator employing low-loss capacitively-loaded traveling-wave electrodes terminated by an on-chip resistor is demonstrated, with 6-dB electrical bandwidth over 150 GHz, ultra-flat electro-optic response and low half-wave voltage of 2 V.
We present a meandered thin-film lithium niobate modulator with <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$1-\mu m$</tex> -gap T-rails for strong and direction-controllable electric field. A record-low half-wave voltage of 0.72 V is achieved on compact footprint xmlns:xlink="http://www.w3.org/1999/xlink">$8\times 1.2\ mm^{2}$</tex> .