A5007212041- Nonlinear Photonic Systems
- Quantum Mechanics and Non-Hermitian Physics
- Antenna Design and Analysis
- Advanced Antenna and Metasurface Technologies
- Photonic and Optical Devices
- Advanced Fiber Laser Technologies
- Neural Networks and Reservoir Computing
- Photonic Crystal and Fiber Optics
- Advanced Wireless Communication Technologies
- Optical Network Technologies
- Advanced Memory and Neural Computing
- Electromagnetic Compatibility and Measurements
- Metamaterials and Metasurfaces Applications
- Advanced MIMO Systems Optimization
- Phase-change materials and chalcogenides
- Satellite Communication Systems
- Solid State Laser Technologies
- Electromagnetic Scattering and Analysis
- Spectroscopy Techniques in Biomedical and Chemical Research
- Energy Harvesting in Wireless Networks
- Topological Materials and Phenomena
- Glass properties and applications
- Advanced Fiber Optic Sensors
- Semiconductor Lasers and Optical Devices
- Spectroscopy and Chemometric Analyses
University of Nottingham
2016-2025
Green University of Bangladesh
2024
George Institute for Global Health
2013-2014
The design of 6th Generation (6G) wireless networks points towards flexible connect-and-compute technologies capable to support innovative services and use cases. Targeting the 2030 horizon, 6G are poised pave way for sustainable human-centered smart societies vertical industries, such that will be transformed into a distributed connectivity infrastructure, where new terminal types embedded in daily environment. In this context, RISE-6G project aims at investigating solutions capitalize on...
The reconfigurable intelligent surface (RIS) is an emerging technology that changes how wireless networks are perceived, therefore its potential benefits and applications currently under intense research investigation. In this letter, we focus on electromagnetically consistent models for RISs inheriting from a recently proposed model based mutually coupled loaded wire dipoles. While existing related focuses free-space channels thereby ignoring interactions between RIS scattering objects...
The paper reports on the coupling of Parity-Time (PT)-symmetric whispering gallery resonators with realistic material and gain/loss models. Response PT system is analyzed for case low high gain dispersion, also two practical scenarios when pump frequency not aligned resonant desired mode there imbalance in profile. results show that presence dispersion misalignment causes skewness bifurcation significant reduction breaking point, respectively. Finally, we demonstrate a lasing operation which...
This Letter, to the best of our knowledge, reports mid-infrared fiber lasing beyond 5 µm at room temperature for first time, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:msup> <mml:mi mathvariant="normal">C</mml:mi> mathvariant="normal">e</mml:mi> </mml:mrow> <mml:mn>3</mml:mn> <mml:mo>+</mml:mo> </mml:msup> </mml:math> -doped, chalcogenide glass, step index employed in-band pumping with a 4.15 quantum cascade laser. The...
Artificial intelligence (AI) drives the creation of future technologies that disrupt way humans live and work, creating new solutions change we approach tasks activities, but it requires a lot data processing, large amounts transfer, computing speed. It has led to growing interest research in developing type platform which is inspired by architecture brain specifically those exploit benefits offered photonic technologies, fast, low-power, larger bandwidth. Here, based on reservoir exploiting...
This paper reports on time-domain modeling of an optical switch based the parity–time (PT) symmetric Bragg grating. The switching response is triggered by suddenly gain in grating to create a PT-symmetric Transient and dynamic behaviors PT gratings are analyzed using numerical transmission line method including simple saturation model. on/off ratio time terms level introduced system operating frequency. also discusses effect has operation gratings.
We report on the impact of realistic gain and loss models bistable operation nonlinear parity-time (PT) Bragg gratings. In our model we include both dispersive saturable show that levels gain/loss saturation can have a significant PT grating based GaAs material. The hysteresis is analyzed for different levels. high improve by reducing intensity at which bistability occurs. However, when low, inhibits characteristics grating.
Abstract A design framework to implement non-unitary input–output operations a practical unitary photonic integrated circuit is described. This achieved by utilising the cosine-sine decomposition recover unitarity of original operation. The recovered operation decomposed into fundamental building blocks, forming network based on directional couplers and waveguide phase shifters. individual blocks are designed optimised three-dimensional full-wave simulations scaled up using approach. paper...
A procedure to achieve near-field multiple input output (MIMO) communication with equally strong channels is demonstrated in this paper. This has applications wireless communications, such as Chip-to-Chip (C2C) or links between printed circuit boards. Designing the architecture of these C2C networks is, however, based on standard engineering design tools. To attain goal, a network optimization proposed, which introduces decoupling and matching networks. As demonstration, applied 2-by-2 MIMO...
Abstract Rare-earth ion doped, silica glass, optical fibre amplifiers have transformed the world by enabling high speed communications and Internet. Fibre lasers, based on rare-earth doped glass fibres, achieve powers are exploited in machining, sensing medical surgery. However, chemical structure of fibres limits wavelength laser operation to < 2.5 µm, which excludes mid-infrared longer range 3–50 µm. doping fluoride glasses enables manufacture lasers up a limiting 3.92 µm wavelength,...
Abstract In this paper a practical case of finite periodic Parity Time chain made resonant dielectric cylinders is considered. The analyzes more general where PT symmetry achieved by modulating both the real and imaginary part material refractive index along resonator chain. band-structure chains compared to infinite in order understand complex interdependence Bloch phase amount gain/loss system that causes break. results show type modulation unit cell can significantly affect position...
The Random Coupling Model (RCM) has been successfully applied to predicting the statistics of currents and voltages at ports in complex electromagnetic (EM) enclosures operating short wavelength limit. Recent studies have extended RCM systems multi-mode aperture-coupled enclosures. However, as size (as measured wavelengths) a coupling aperture grows, matrix used increases well, computation becomes more time-consuming. A simple Power Balance (PWB) can provide fast predictions for...
This Roadmap takes the reader on a journey through research in electromagnetic wave propagation control via reconfigurable intelligent surfaces. Meta-surface modelling and design methods are reviewed along with physical realisation techniques. Several wireless applications discussed, including beam-forming, focusing, imaging, localisation, sensing, some rooted novel architectures for future mobile communications networks towards 6G.
The process for developing an accurate and reliable classification model based on the previously pre-processed data. performance of each is assessed using Matthew's Correlation Coefficient as a metric.
A new embedded model for curved thin panels is developed in the Transmission Line Modeling (TLM) method. In this model, are first linearized and then between adjacent 2D TLM nodes allowing arbitrary positioning node centers. The eliminates necessity fine discretization thus reducing run time memory requirements calculation. accuracy convergence of verified by comparing resonant frequencies an elliptical cylinder formed using carbon fiber composite (CFC) materials with those equivalent metal...
Abstract Comprehensive numerical tools to investigate and analyze the surface wave attenuation on a metasurface waveguide that consists of periodic patches deposited dielectric substrate are presented. The is evaluated in both open‐space environments at high frequencies around 28‐GHz band. Two approaches including driven modal approach an integrated eigenmode for investigating behaviors operating transverse electromagnetic (TEM) mode employed. These results show different values depending...
A fully bio-inspired apparatus to perform non-spectroscopic sensing discriminate, and determine the constituent concentrations of a chemical mixture is proposed. Here, means that it comprised biomimetic sensor neuromorphic signal processor. The similar human eye in terms its trichromat architecture overlapping spectral response. information processor system based on an electro-optical implementation reservoir computer. time-stepping algorithm Z-bilinear transformation has been developed...
Intravital microscopy using multiphoton processes is the standard tool for deep tissue imaging inside of biological specimens. Usually, near-infrared and infrared light used to excite sample, which enables several mean free path a scattering tissues. Using longer wavelengths, however, increases width effective Point Spread Function (PSF). Many features cells tissues are smaller than diffraction limit, therefore not possible distinguish large PSF. Microscopy high refractive index microspheres...
Understanding the impact of interference upon performance a multiple input output (MIMO) based device is paramount importance in ensuring design both resilient and robust. In this work effect element-element creation channels wireless link approaching near-field regime studied. The elements 2-antenna transmit- receive-arrays are chosen to be identical folded dipole antennas operating at 5.6 GHz. We find that two equally strong can created even if interact sub-wavelength distances, thus...