A5100711778- Photonic and Optical Devices
- Advanced Fiber Laser Technologies
- Photonic Crystals and Applications
- Photorefractive and Nonlinear Optics
- Orbital Angular Momentum in Optics
- Plasmonic and Surface Plasmon Research
- Optical Network Technologies
- Nonlinear Optical Materials Studies
- Laser-Matter Interactions and Applications
- Metamaterials and Metasurfaces Applications
- Advanced Photonic Communication Systems
- Near-Field Optical Microscopy
- Advanced Computational Techniques and Applications
- Mechanical and Optical Resonators
- Plant Reproductive Biology
- Nonlinear Photonic Systems
- Optical Coatings and Gratings
- Simulation and Modeling Applications
- Quantum chaos and dynamical systems
- Gaussian Processes and Bayesian Inference
- Neural Networks and Reservoir Computing
- Semiconductor Quantum Structures and Devices
- Mathematical Biology Tumor Growth
- Distributed Sensor Networks and Detection Algorithms
- Gene Regulatory Network Analysis
University of Bristol
2014-2023
Tsinghua University
2023
Sun Yat-sen University
2015-2021
State Key Laboratory of Optoelectronic Materials and Technology
2019
South China Normal University
2019
South China University of Technology
2019
University of Glasgow
2015
The coherent transmission technology using digital signal processing and advanced modulation formats, is bringing networks closer to the theoretical capacity limit of optical fibres, Shannon limit. in-phase quadrature electro-optic modulator that encodes information on both amplitude phase light, one underpinning devices for technology. Ideally, such should feature low loss, drive voltage, large bandwidth, chirp compact footprint. However, these requirements have been only met separate...
Harnessing the orbital angular momentum (OAM) of light is an appealing approach to developing photonic technologies for future applications in optical communications and high-dimensional quantum key distribution (QKD) systems.An outstanding challenge widespread uptake OAM resource its efficient generation.In this work we design a new device that can directly emit OAM-carrying beam from low-cost semiconductor laser.By fabricating micro-scale spiral phase plates within aperture vertical-cavity...
Applications of quantum walks can depend on the number, exchange symmetry and indistinguishability particles involved, underlying graph structures where they move. Here, we show that silicon photonics, by exploiting an entanglement-driven scheme, realize with full control over all these properties in one device. The device implements entangled two-photon any five-vertex graph, continuously tunable particle indistinguishability. We how this simulates single-particle larger graphs, size...
We propose and demonstrate a hybrid silicon lithium niobate Michelson interferometer modulator (MIM) with reduced half-wave voltage-length product compared to Mach-Zehnder modulator. The is based on seamless integration of high-contrast waveguide niobate—a widely used material—with compact, low-loss circuitry. present device demonstrates as low 1.2 V cm insertion loss 3.3 dB. 3 dB electro-optic bandwidth approximately 17.5 GHz. high-speed modulations are demonstrated at 32 Gbit/s 40 the...
We propose and experimentally demonstrate a high-performance polarization splitter-rotator based on the lithium niobate-on-insulator platform, consisting of an adiabatic taper, asymmetric directional coupler, multimode interference mode splitter. Two injecting modes with orthogonal states were separated, transverse magnetic (TM) state was rotated to electric (TE) simultaneously. The designed device is fabricated in single-step etching process, providing extinction ratio 20 dB over 80 nm...
Integrated traveling-wave lithium niobate modulators need relatively large device lengths to achieve low drive voltage. To increase modulation efficiency within a compact footprint, we report an integrated Fabry–Perot-type electro-optic thin film on insulator modulator comprising phase region sandwiched between two distributed Bragg reflectors. The exhibits optical loss and high tuning of 15.7 pm/V. We also confirm the modulator's high-speed performance by non-return-to-zero with data rate...
In this paper, we demonstrate up to 260-GBaud single-wavelength coherent transmission by employing an optical transmitter based on two wide-bandwidth devices: a novel 260-GS/s arbitrary waveform generator with 10-dB bandwidth of 90-GHz and thin-film Lithium Niobate I/Q modulator 3-dB 110-GHz. We first assess the performance our high symbol rate for generating spectrally efficient Nyquist multilevel modulation format signals at rates 210-GBaud >1.4-Tbps achievable information using linear...
3D printing and actively switchable redox-active oligo(aniline)-based materials are combined to create novel tuneable photonic materials. By a direct laser writing process, functional structures with submicrometer features fabricated. Reversible changes in the refractive index of written generated negligible size changes. Actively optical systems evolving as an important research field,1 enabling formation adaptable for application displays2 sensing devices.3, 4 An ideal system would be...
We demonstrate a high-performance reconfigurable bandpass filter implemented by cascaded Sagnac loop mirror (SLM)-based coupled resonator optical waveguides (CROWs) on the silicon-on-insulator platform. By dynamic thermal tuning of reflectivity in each SLM, proposed can achieve simultaneous 3 dB bandwidth from 8.50 to 20.25 GHz and central wavelength range 216.25 GHz. A box-like filtering response with an ultra-high extinction ratio up 70 ultra-sharp roll-off 0.61 are observed 6th-order...
We propose and demonstrate a polarization-insensitive high speed optical switch unit based on silicon lithium niobate hybrid integration platform. The presented device exhibits sub nano-second switching time, low drive voltages of 4.97 V, power dissipation due to electrostatic operation. measured polarization dependence loss was lower than 0.8 dB. demonstrated could provide as building block for high-speed matrix switches.
The characteristics of high-power partially coherent laser beams propagating upwards in the turbulent atmosphere are studied, where principal features diffraction, nonlinear self-focusing and turbulence considered. Based on "thin window" model, analytical propagation formulae derived by using quadratic approximation phase shift. It is found that effect plays an important role beam characteristics. But effects can be suppressed increasing elevation. Furthermore, influence elevation stronger...
We propose a method to directly visualize the photonic band-structure of micrometer-sized crystals using wide-angle spectroscopy. By extending Fourier imaging spectroscopy sensitivity into infrared range, we have obtained accurate measurements band structures along high-symmetry directions (X-W-K-L-U) polymeric three-dimensional, rod-connected diamond crystals. Our implementation also allows us record single-wavelength reflectance far-field patterns showing very good agreement with...
We propose and demonstrate a low-loss fiber-to-chip vertical coupler on the silicon photonic platform by using 3D two-photon fabrication method. Such significantly reduces insertion loss, measured to be 1 dB, provides wide working wavelength range for both TE TM polarizations over entire C-band. Moreover, large tolerance misalignment of coupling fiber, up 4.5 µm dB enables development relaxed alignment techniques.
Vortex beams carrying orbital angular momentum have attracted a great deal of attention over the past few years. An integrated vortex beam generator with high efficiency is desirable for wide-ranging applications. Here we demonstrate highly efficient silicon photonic based on superposed holographic fork gratings. A metal mirror used to enhance emission by reflecting power leaking down substrate back air. Experimental characterization confirms that increases ${\sim} 5\,{\rm dB}$∼5dB....
The uniform irradiation generated by beam self-focusing in the inhomogeneous atmosphere is studied. It found that may appear on propagation of an initial flat-topped from ground to space orbits because phase modulation caused atmosphere. This offer a way achieve under effect nonlinearity. target interesting for laser space-debris clearing. To debris target, we present fitting formula modified focal length, which presents effective design rule target. In addition, influence order quality due...
We experimentally demonstrate ultra-high speed optical modulations up to 120 Gbit/s (120 Gbaud NRZ) and 220 (110 PAM4) based on a lithium niobate insulator (LNOI) modulator, which has 3-dB electro-optical bandwidth of 56 GHz the Vπ 2.6 V.
The analytical propagation formulae of Hermite-Gaussian (H-G) beams propagating in Kerr media are derived by using the variational approach. self-focusing critical power, Rayleigh range and beam quality factor H-G also derived. It is demonstrated that ABCD law valid if a new complex parameter introduced, which presents simple method to study through an optical system media. shown that, as order increases, power increase less affected nonlinearity. Finally, it found focus point never appears...
We show that it is possible to confine light in a volume of order 10−3 cubic wavelengths using only dielectric material. Low-index (air) cavities are simulated high-index rod-connected diamond photonic crystals. These long storage times (Q-factors >106) even at the lowest volumes. Fabrication such structures could open new field photon-level interactions.
An integrated approach to thermal modulation of relative phase between two optical vortices with opposite chirality has been demonstrated on a silicon-on-insulator substrate. The device consists silicon-integrated vortex emitter and controlled 3 dB coupler. can be actively modulated chip by applying voltage the heater. shift is shown linearly proportional applied electrical power, rotation angle interference pattern observed inversely topological charge. This scheme used in lab-on-chip,...
We propose and demonstrate a polarization diversity two-dimensional grating coupler based on the lithium niobate insulator platform, for first time, to best of our knowledge. The optimization design, performance characteristics, fabrication tolerance are thoroughly analyzed utilizing three-dimensional finite-difference time-domain method. Experimentally, -7.2 dB coupling efficiency is achieved with 1 bandwidth 64 nm. polarization-dependent loss about 0.4 around 1550 Our work provides new...
To achieve the modification of photonic band structures and realize dispersion control toward functional devices, composites crystal templates with high-refractive-index material are fabricated. A two-step process is used: 3D polymeric woodpile fabricated by a direct laser writing method followed chemical vapor deposition MoS2. We observed red-shifts partial bandgaps at near-infrared region when thickness deposited MoS2 films increases. ∼10 nm red-shift fundamental high-order bandgap...
A tunable grating coupler capable of dynamically changing the central wavelength with low power consumption is demonstrated and fabricated using a standard complementary metal-oxide-semiconductor process. The based on an efficient thermal tuning scheme employing free-standing silicon-on-insulator strip waveguides. air gap provides isolation between heated structure underlying silicon substrate, which greatly enhance heating efficiency. We achieve shift 55 nm for 19.5 mW record efficiency...
Three-dimensional complete photonic bandgap materials or crystals block light propagation in all directions. The rod-connected diamond structure exhibits the largest known to date and supports a for lowest refractive index contrast ratio down nhigh/nlow ∼ 1.9. We confirm this threshold by measuring infrared region Sn–S–O (n 1.9) Ge–Sb–S–O 2) inverse structures. structures were fabricated using low-temperature chemical vapor deposition process via single-inversion technique. This provides...