A5083748334- Photonic and Optical Devices
- Optical Coatings and Gratings
- Advanced Fiber Optic Sensors
- Photonic Crystals and Applications
- Optical Network Technologies
- Plasmonic and Surface Plasmon Research
- Semiconductor Lasers and Optical Devices
- Advanced Fiber Laser Technologies
- Phase-change materials and chalcogenides
- Intermetallics and Advanced Alloy Properties
- Advanced Photonic Communication Systems
- Photonic Crystal and Fiber Optics
- MXene and MAX Phase Materials
- Liquid Crystal Research Advancements
- Magneto-Optical Properties and Applications
- EEG and Brain-Computer Interfaces
- Quasicrystal Structures and Properties
- Neural Networks and Reservoir Computing
- Gyrotron and Vacuum Electronics Research
- Microwave Engineering and Waveguides
- Blind Source Separation Techniques
- Laser-Matter Interactions and Applications
- Electromagnetic Simulation and Numerical Methods
- Gaze Tracking and Assistive Technology
- Semiconductor Quantum Structures and Devices
Nankai University
2025
Shenyang Aerospace University
2024
Hisense (United States)
2020-2024
Qufu Normal University
2021-2022
Craft Group (China)
2022
Chongqing University
2022
Massachusetts Institute of Technology
2012-2019
McMaster University
2007-2012
Uropathogenic Escherichia coli (UPEC) is a major cause of urinary tract infections (UTIs). Invasion into bladder epithelial cells (BECs) on the luminal surface via type 1 fimbria first critical step in UPEC infection. Although expression increases during invasion BECs, underlying regulatory mechanisms remain poorly understood. This study reported previously uncharacterized two-component system (TCS) GrpP/GrpQ that directly activates to promote and therefore pathogenicity response D-serine...
A coupled-mode formulation is described in which the radiation fields are represented terms of discrete complex modes. The modes obtained from a waveguide model facilitated by combination perfectly matched boundary (PML) and reflecting (PRB) condition. By proper choice PML parameters, guided structure remain unchanged, whereas continuous discretized into orthogonal normalizable quasi-leaky identical to that for waveguides with loss and/or gain can be solved similar analytical numerical...
This paper reports theoretical designs and simulations of electrooptical 2 × switches 1 loss modulators based upon GST-embedded SOI channel waveguides. It is assumed that the amorphous crystalline phases GST can be triggered electrically by Joule heating current applied to a 10-nm film sandwiched between doped-Si waveguide strips. TEo TMo mode effective indices are calculated over 1.3 2.1-μm wavelength range. For Mach-Zehnder directional coupler switches, low insertion loss, crosstalk, short...
We show that octave-spanning Kerr frequency combs with improved spectral flatness of comb lines can be generated in dispersion-flattened microring resonators. The resonator is formed by a strip/slot hybrid waveguide, exhibiting flat and low anomalous dispersion between two zero-dispersion wavelengths are separated one octave from near-infrared to mid-infrared. Such flattened profiles allow for the generation mode-locked combs, using relatively pump power obtain two-cycle cavity solitons on...
A rigorous full-vector analysis based on the finite-difference mode-matching method is presented for three-dimensional optical wave propagation problems. The computation model facilitated by a perfectly matched layer (PML) terminated with reflecting boundary condition (PRB). complex modes including both guided and radiation fields of waveguide arbitrary index profiles are computed scheme. applied to validated facet reflectivity buried power exchange periodically loaded dielectric...
We demonstrate an ultra-subwavelength surface plasmonic polaritons waveguide, which can confine light in the nano-scale region with comparable low propagation loss. The mode be squeezed to one thousandth of diffraction spot size micro-meter scale distance and is highly sensitive buffer layer materials geometric parameters. This design improves performance previous waveguides lends itself complementary metal–oxide–semiconductor compatible fabrication. These used as a platform for active...
Theoretical modeling and numerical simulation have been performed at λ=2100 nm on silicon-on-insulator channel-waveguide directional couplers in which the outer two Si waveguides are passive central waveguide(s) electro-optical (EO) "islands." The EO channel(s) utilize a 10 layer of Ge2Sb2Te5 phase-change-material sited midlevel doped channel. A voltage-driven phase change produces large effective index TEo TMo modes, thereby inducing crossbar 2×2 switching. mode-matching method is employed...
New designs for electro-optical free-space and waveguided 2 x switches are presented analyzed at the 1.55 μm telecoms wavelength. The proposed devices employ a ~10 nm film of GeSe that is electrically actuated to transition layer forth-and-back from amorphous crystal phase, yielding switch with two self-sustaining states. This phase change material was selected its very low absorption loss operation wavelength, along electro-refraction Δn ~0.6. All cascadeable into N M devices. prism-shaped...
A low-loss Bragg grating structure based on insulator-metal-insulator surface plasmonic waveguide is investigated theoretically. Performance of the gratings simulated by rigorous numerical methods and interesting features, such as low scattering absorption losses more symmetrical reflection spectra, etc., are demonstrated against key design parameters.
We introduce an efficient design approach for Ultraviolet (UV) band-pass filter based on metal-dielectric stacks. present a general method and then apply this to two special cases: UV band pass (i) Al/Al2O3 stacks as well (ii) Ag/SiO2 As experimental confirmation, we fabricate with three layer pairs fused silica substrate (Corning 7980), targeting central wavelength of 320 nm. A measurement at the peak shows transmission efficiency high 67% in our filter.
A compact Bragg grating with embedded gapped metallic nano-structures is proposed and investigated theoretically. The consists of periodic planar strips in a dielectric waveguide. exhibits distinct polarization characteristics due to its underlying working mechanisms the nano-strips. can be considered as insulator-metal-insulator surface plasmonic polariton waveguide improved light confinement for TM polarized waves. For TE waves, significant field mismatch between metal non-metal sections...
Silicon-on-nitride (SON) is a convenient, low-loss platform for mid-infrared group IV plasmonics and photonics. We have designed 5-layer SON channel-waveguides slab-waveguides the 2.0 to 5.4 μm wavelength range simulated resulting three-dimensional (3D) two-dimensional (2D) gap-plasmon modes. Our simulations show propagation lengths of ∼60 3D gap-strip modes having 0.003 λ2 cross-section. Because ∼50-nm (Si3N4) mode region also gate insulator between silver (Ag) n-doped Silicon (Si),...
We present an analysis on intra-cavity dispersion of a micro-resonator. As example, different sources silicon nitride microring resonator are identified and evaluated over wide wavelength range. also show the flattening technique based strip/slot hybrid waveguide structure can be used to tailor dispersions. Octave-spanning Kerr frequency combs numerically simulated using 2-D-FDTD. It is shown that 7.5-fs two-cycle cavity solitons generated, enabling ultrawide mode-locked combs, with improved...
Automatic seizure detection system can serve as a meaningful clinical tool for the treatment and analysis of epilepsy using electroencephalogram (EEG) has obtained rapid development. An automatic epileptic method based on kernel-based robust probabilistic collaborative representation (ProCRC) combined with graph-regularized non-negative matrix factorization (GNMF) is proposed in this work. The raw EEG signals are pre-processed through wavelet transform to obtain time-frequency distribution...
The complex mode-matching method is applied to simulation of optical waveguide structures with intersecting such as crossings and corners. It demonstrated that field propagating along the direction perpendicular incident can be represented adequately by modes defined in and, therefore, simulated accurately method. Power conservation illustrated way examples prove self-consistency Radiation axis corners this validated finite-difference time-domain
Waveguide Bragg grating structures with strong index corrugations are analyzed by the complex mode-matching method. As corrugation increases, peak wavelength of reflection spectrum is shifted towards shorter from conventional condition due to energy storage effect. It shown that corresponds center stop-band Floquet-Bloch mode. An efficient and reliable iterative method proposed for design corrugations.
The complex coupled-mode theory (CMT) is applied to optical fiber grating structures of circular cross section. radiative fields are treated in terms discrete modes similarly the guided conventional CMT. number that contribute couplings may be effectively reduced by considering phase-matching condition. Therefore, simple analytical expressions for mode amplitudes and powers obtained. Examples Bragg gratings with various outer cladding refractive indexes, e.g., lower, equal higher than inner...
A coupled-mode formulation based on complex local modes is developed for tapered and longitudinally varying optical waveguides. Different from the conventional theory that requires integration over entire spectrum of radiation modes, new treats fields via discrete similarly to guided modes. Accuracy, convergence, scope validity solutions equations are investigated in detail a typical single-mode waveguide taper. It demonstrated has overcome difficulties simulation field effects while...
We propose an electrically driven nanometer scale plasmonic optical latch integrated with Ge2Sb2Te5 chalcogenide glasses. For effective switching length of 167 nm, the extinction ratio between ON and OFF states proposed switch is as large 10 dB, net operation energy low 30.4 pJ per cycle.
A rigorous circuit model for the simulation of large-scale photonic integrated (PIC) is proposed and validated. Different from conventional theory, both guided radiation fields are taken into consideration in model. PIC arbitrary size complexity partitioned a collection basic elements interconnected via physical virtual ports. The parameters describing terminal properties extracted by numerical techniques device such as FDTD method. performance entire can be simulated algorithms based on...
Two fundamental principles of the mode-matching method-mode orthogonality and tangential field continuity conditions have been revisited in depth. With a finite number modes employed conventional method, condition at waveguide-discontinuity interface fails leading to mismatch error. We propose an alternate, superior method implemented by reconstruction auxiliary coefficient matrix, rather than applying above-mentioned orthogonality. Detailed transfer-matrix equations derived for...
In this paper, the stress-strain curves of Ti2AlNb are established based on uniaxial impact tests over wide ranges temperature and strain rate. The exhibited work hardening effect but did not show an obvious yield stage during a quasi-static compression test. SHPB test, softening was found, rate strengthening detected when 4000-8000 s-1, in range 8000-12,000 s-1. A function describing parameters under various temperatures proposed to modify basic J-C constitutive model. relative errors...