Article
Optics
Cameron M. Naraine, Jocelyn N. Westwood-Bachman, Cameron Horvath, Mirwais Aktary, Andrew P. Knights, Jens H. Schmid, Pavel Cheben, Jonathan D. B. Bradley
Summary: Subwavelength grating (SWG) metamaterial waveguides and ring resonators on a silicon nitride platform are proposed and demonstrated. The SWG waveguide achieves a large overlap (53%) of the Bloch mode with the top cladding material, showing great potential for evanescent field sensing and light amplification. Fabricated using a commercial rapid turn-around silicon nitride prototyping foundry process, the devices have critical dimensions greater than 100 nm. Experimental characterization reveals excellent internal quality factor (2.11 x 10(5)) and low propagation loss (approximately 1.5 dB cm(-1)) in the C-band, surpassing silicon-based SWG ring resonators. These results demonstrate the promising prospects of SWG metamaterial structures for silicon nitride based photonic integrated circuits.
LASER & PHOTONICS REVIEWS
(2023)
Article
Engineering, Electrical & Electronic
Alexander Chen, Amir Begovic, Stephen Anderson, Zhaoran Rena Huang
Summary: Si photonic foundry fabricated cascaded and continuous spiral shaped silicon nitride waveguides with Bragg grating structures to achieve on-chip true-time delay line. Time-domain measurement method was used to characterize the delay time, and the highest group index extracted from cascaded SiN grating waveguides is 19.7, while the continuous spiral SiN grating waveguide produces a delay time of 3.78 ns.
IEEE PHOTONICS JOURNAL
(2022)
Article
Engineering, Electrical & Electronic
Kazim Gorgulu, Emir Salih Magden
Summary: This study presents the design, simulation, and experimental demonstration of compact and ultra-broadband silicon photonic filters with adiabatic waveguides. The filters can separate a broadband signal into short-pass and long-pass outputs using an optimization algorithm for coupled adiabatic waveguide structures. The experimentally demonstrated band-pass filters have passbands ranging from 6.4 nm up to 96.6 nm, with low insertion loss and high extinction ratios.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2023)
Article
Optics
Tianhang Lian, Mu Zhu, Shijie Sun, Xueqing Sun, Yuanhua Che, Baizhu Lin, Xibin Wang, Daming Zhang
Summary: A mode-selective modulator and switch have been developed for independent modulation or switching of different modes in a few-mode waveguide, using a graphene-polymer hybrid platform. The method offers flexibility and efficiency in managing spatial modes.
Article
Optics
Manuel Ackermann, Florian Merget, Jeremy Witzens
Summary: Silicon photonics ring resonators play a crucial role in wavelength-division-multiplexed communication networks. However, bending losses become unacceptable when the circumference is reduced below a few micrometers. This paper proposes the use of a sub-wavelength tunneling barrier at the critical radius to suppress these losses without significantly increasing the resonator's resistance.
Article
Engineering, Electrical & Electronic
Jingquan Xu, Kexin Chen, Yingying Qu, Chen Liu, Songnian Fu, Deming Liu
Summary: This article presents a novel double gratings configuration based on LCOS optical filter, which achieves higher spectral resolution by enlarging and accumulating dispersion. With this configuration, a spectral resolution of 1.63 GHz is achieved, almost tenfold enhancement compared to traditional single grating configuration.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Denis M. Fatkhiev, Vladimir S. Lyubopytov, Ruslan V. Kutluyarov, Elizaveta P. Grakhova, Albert K. Sultanov
Summary: A design approach for a grating coupler (GC) enabling generation and propagation of quasi-TE vortex modes within photonic integrated circuits (PICs) has been proposed and numerically verified. The optimized GC design parameters maximize the purity of orbital angular momentum (OAM) mode, achieving over 96% purity of the target OAM state +/- 1 at 1550 nm wavelength. Compatibility with standard nanofabrication processes makes this design a simple, compact, and robust solution for various potential PIC-based applications of OAM beams.
IEEE PHOTONICS JOURNAL
(2021)
Article
Multidisciplinary Sciences
Myungjae Lee, Hanyu Hong, Jaehyung Yu, Fauzia Mujid, Andrew Ye, Ce Liang, Jiwoong Park
Summary: This paper reports three-atom-thick waveguides, called delta waveguides, based on wafer-scale molybdenum disulfide (MoS2) monolayers, which can guide visible and near-infrared light over millimeter-scale distances with low loss and efficient in-coupling. The extreme thinness of the waveguides enables a light-trapping mechanism similar to a delta-potential well in quantum mechanics, allowing for guided waves that propagate freely along the in-plane direction but are confined along the out-of-plane direction. The integration of thin-film optical components with delta waveguides demonstrates key functionalities essential for two-dimensional photonics.
Article
Engineering, Electrical & Electronic
Hao Sun, Bruno Taglietti, Yue Wang, Lawrence R. Chen
Summary: Bragg gratings (BGs) are widely used in microwave photonic signal processing and systems due to their customizable amplitude and phase responses. Waveguide BGs (WBGs) are compact and easily integrated with other components to build MWP systems. Subwavelength grating (SWG) waveguides and passive devices in silicon-on-insulator (SOI) have enabled the development of breakthrough devices based on anisotropic metamaterials.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Chemistry, Multidisciplinary
Yitong Gu, Ning Wang, Haorui Shang, Fei Yu, Lili Hu
Summary: This study investigates the influence of gratings on the coupling efficiency of waveguides through theoretical models and numerical simulations. The research finds that carefully designed gratings can significantly improve the wide-angle input efficiency of waveguides. It provides guidance for simulating the effects of gratings on the light-gathering abilities of waveguides and has potential applications in fields such as bioanalytical instrumentation and quantum photon probes.
Article
Engineering, Electrical & Electronic
Haosen Tan, Weida Zhang, Yudong Chen, Yuhe Xia, Chris Newey, Tso-Min Chou, Nai-Hsiang Sun, Jerome K. K. Butler, Gary A. A. Evans
Summary: This study presents a simple thin film effective index analysis for first-order gratings in Si photonic waveguides, which can provide highly accurate results for reflected and transmitted power spectrums as long as the waveguide remains single mode and non-radiating. It is also found that adding a cover layer to the grating region can modify the grating's strength and the width of the reflectivity spectrum.
IEEE PHOTONICS JOURNAL
(2022)
Article
Engineering, Electrical & Electronic
Claudio Porzi, Manuel Reza, Paolo Ghelfi, Marc Sorel, Antonella Bogoni
Summary: We report a silicon photonics flat-top bandpass microwave photonic filter with large out-of-band power rejection of over 40 dB and tunability of central frequency up to 70 GHz. The RF bandpass transfer function can be widely configured without sacrificing filter performance. The filter integrates a phase modulator and a tunable optical splitter to achieve a high level of functional integration.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2022)
Article
Optics
Tiancheng Gu, Shuozhe Xu, Xin Zhang, Kangni Wang, Linyong Qian
Summary: This study demonstrates the achievement of hybrid resonance modes by introducing symmetry-breaking into a guided-mode resonance grating. The transformation of BICs into quasi-BICs with a high-quality factor is achieved while maintaining the intrinsic GMR mode. The resonance occurs at the pump and emission wavelengths of the gain medium, resulting in low-threshold laser action.
Article
Optics
Thi Thuy Duong Dinh, Xavier Le Roux, Natnicha Koompai, Daniele Melati, Miguel Montesinos-Ballester, David Gonzalez-Andrade, Pavel Cheben, Aitor V. Velasco, Eric Cassan, Delphine Marris-Morini, Laurent Vivien, Carlos Alonso-Ramos
Summary: Integrated mid-infrared micro-spectrometers show great potential for environmental monitoring and space exploration. The use of silicon-on-insulator (SOI) as a platform for integration is promising due to its capability for large volume and low-cost production of compact photonic circuits. However, the limitation of the strong absorption of the buried oxide layer in SOI for wavelengths beyond 4 μm is overcome by utilizing metamaterial-cladded suspended silicon waveguides to implement a spatial heterodyne Fourier-transform (SHFT) spectrometer operating at wavelengths near 5.5 μm.
Article
Optics
Lorenz Weiss, Andreas Gritsch, Benjamin Merkel, Andreas Reiserer
Summary: Resonant spectroscopy of erbium implanted into nanophotonic silicon waveguides reveals 1 GHz inhomogeneous broadening and homogeneous linewidths below 0.1 GHz, introducing a promising materials platform for on-chip quantum information processing.
Editorial Material
Engineering, Electrical & Electronic
Brajesh Kumar Kaushik
CIRCUITS SYSTEMS AND SIGNAL PROCESSING
(2023)
Article
Biochemical Research Methods
Yu Wang, Ragini Singh, Muyang Li, Rui Min, Qiang Wu, Brajesh Kumar Kaushik, Rajan Jha, Bingyuan Zhang, Santosh Kumar
Summary: The article presents the development of a hetro-core optical fiber sensor using localized surface plasmon resonance (LSPR) to detect cardiac troponin I (cTnI) solution. The sensor structure consists of a single-mode fiber - multimode fiber - single-mode fiber (SMS) structure, immobilized with gold and cerium oxide nanoparticles. The sensor has a linear range of 0-1000 ng/mL cTnI, a sensitivity of 3 pm/(ng/mL), and a detection limit of 108.15 ng/mL. It will be used in real-time to detect acute myocardial infarction (AMI).
IEEE TRANSACTIONS ON NANOBIOSCIENCE
(2023)
Article
Public, Environmental & Occupational Health
Sanjay Saint, M. Todd Greene, Sarah L. L. Krein, Karen E. E. Fowler, Kathleen A. A. Linder, David Ratz, Jennifer Meddings
Summary: This study aimed to investigate the changes in device-associated infection prevention practices during the COVID-19 pandemic. Data collected mid-pandemic were used to assess the use of several infection prevention practices and compare them with historical data. The results showed that the use of preventive practices for CLABSI and VAE continued to increase or plateau, while the use of preventive practices for CAUTI decreased.
INFECTION CONTROL AND HOSPITAL EPIDEMIOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Saurabh Kharwar, Sangeeta Singh, Brajesh Kumar Kaushik
Summary: This paper investigates the structural, electronic, and transport properties of cove-edge aluminum nitride nanoribbons (AlNNR) using density functional theory and the non-equilibrium Green's function (NEGF) method. The results show that the cove-edge AlNNRs are thermodynamically stable and exhibit metallic behavior. The calculated current-voltage characteristics of the cove-edge AlNNR-based nanodevices exhibit negative differential resistance (NDR) and high peak-to-valley current ratio (PVCR).
Article
Optics
Weicheng Chen, Dian Wan, Qi He, Jiaqi Wang, Haofeng Hu, Tiegen Liu, Hon Ki Tsang, Zhenzhou Cheng
Summary: Short-wavelength mid-infrared (MIR) silicon photonics has various applications in optical communications, chemical analysis, and environmental monitoring. In this study, a relaxed-tolerance subwavelength grating (SWG) coupler design with dual-hole structures was demonstrated to overcome fabrication variations and improve reproducibility. The relaxed-tolerance SWG coupler achieved a peak coupling efficiency of -6.2 dB at a wavelength of 2.038 μm with a 1-dB bandwidth of about 30 nm.
OPTICS AND LASER TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
M. Sankush Krishna, Sangeeta Singh, Brajesh Kumar Kaushik
Summary: In this study, we investigate the potential of magnesium oxide nanoribbons (MgONRs) for spintronic applications using density functional theory (DFT) and nonequilibrium Green's function (NEGF). We find that the considered MgONRs are thermodynamically stable and exhibit different magnetic properties. We also report the transport characteristics and spin filtering efficiency of hydrogenated MgONRs, as well as the giant magnetoresistance observed in one specific MgONR. These findings suggest that MgONRs are promising candidates for future spintronics technology.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Engineering, Electrical & Electronic
Seema Dhull, Arshid Nisar, Vikas Nehra, Sanjay Prajapati, T. Nandha Kumar, Brajesh Kumar Kaushik
Summary: This article proposes a three-bit SOT-MRAM-based MLC structure called TLC, which effectively addresses the issues of write disturb rate and large writing step counts in MLCs. Most bits in TLC require two steps of writing for storage, and the cell exhibits a WDR of less than 10(-8). Performance evaluation using the SPICE framework shows that the proposed TLC device is 96% and 92% more energy efficient than STT-based TLC and STT-/SOT-based TLC structures, respectively. The worst case write latency of the TLC is 2 ns, showing an 88% improvement compared to the recently published STT-/SOT-based TLC-MRAM. Variability analysis using Monte Carlo simulations demonstrates sufficient margins for reliable switching of different bits in the TLC by employing various writing currents to switch the stacked MTJs.
IEEE TRANSACTIONS ON MAGNETICS
(2023)
Article
Nanoscience & Nanotechnology
Sandeep Soni, Gaurav Verma, Hemkant Nehete, Brajesh Kumar Kaushik
Summary: Convolutional neural networks (CNNs) offer a more accurate alternative for deep learning tasks, but conventional CMOS based devices still lag in area and energy efficiency. Unconventional devices, circuits, and architectures have been investigated to mimic the functionality of neurons and synapses for neuromorphic applications. This study utilizes the spin-orbit torque magnetic tunnel junction (SOT-MTJ) device for activation and max-pooling, reducing the need for dedicated hardware. The MAAP based CNN architecture shows significant reductions in read/write operations, improving area and energy efficiency compared to conventional designs.
IEEE OPEN JOURNAL OF NANOTECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Hedong Liu, Xiaobo Li, Zhenzhou Cheng, Tiegen Liu, Jingsheng Zhai, Haofeng Hu
Summary: Color polarimetric imaging provides multidimensional information for object properties and has various applications. However, polarimetric images have lower SNR and are more sensitive to noise than conventional color images, leading to noisy images and degraded polarization analysis. In this article, a 3-D CNN is proposed to denoise color polarimetric images by utilizing the coherence among space, color, and polarization. Experiments show that this method effectively removes noise and restores polarization information, suggesting potential applications in multidimensional imaging tasks.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2023)
Article
Engineering, Electrical & Electronic
M. Sankush Krishna, Sangeeta Singh, Brajesh Kumar Kaushik
Summary: Density functional theory (DFT) calculations were performed to investigate the structural, electronic, and transport characteristics of hydrogen/fluorine edge-passivated stanene nanoribbons (SnNRs) as metal interconnect. The results showed that fluorination enhanced the thermodynamic stability of SnNRs, and their band structure and density of states confirmed their metallic nature, making them promising candidates for nanoscale metal interconnect applications. The non-equilibrium Green's function (NEGF) formalism was used for quantum transport calculations, and the parasitic parameters influencing interconnect performance were evaluated. The obtained findings, along with the evaluation of performance metrics using a DIL circuit model, suggested that SnNRs can be considered as promising candidates for nanoscale metal interconnect applications.
IEEE TRANSACTIONS ON NANOTECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Shipra Saini, Namita Bindal, Brajesh Kumar Kaushik
Summary: Using first-principle calculations, the authors observe variations in magnetic anisotropy energy and other magnetic properties for transition metal (TM) doped bismuth monolayer. The Mn-doped bismuthene exhibits half-metallicity with higher magnetic moment and magnetic anisotropy energy compared to Fe-doped and Ti-doped systems. The half-metal Mn-Bi can induce half-metallicity in CrI3 through charge transfer, making it the most favorable doped system for spintronic device development in Mn-Bi/CrI3 van der Waals heterostructure.
IEEE OPEN JOURNAL OF NANOTECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Namita Bindal, Ravish Kumar Raj, Brajesh Kumar Kaushik
Summary: Antiferromagnetic (AFM) skyrmion technology is considered a promising direction for the development of the next-generation spintronics-based neuromorphic computing due to its unique features. In this study, a neuron device based on AFM skyrmion is proposed, which demonstrates integrate fire functionality and generates an output signal on a nanotrack. The proposed device offers a 68% reduction in energy dissipation when the number of skyrmions on the nanotrack is increased from 1 to 3.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
Shipra Saini, Namita Bindal, Brajesh Kumar Kaushik
Summary: This research proposes a neuron based on skyrmionium and utilizes the gradient of perpendicular magnetic anisotropy (PMA) to achieve leaky-integrate-fire (LIF) functionality. The suggested device is reported to be 15.5% more energy-efficient than the AFM skyrmion-based LIF neuron, dissipating 3.74 fJ of energy per LIF operation. This power-efficient artificial neuron potentially enables the development of a dense spiking neuromorphic computing system.
2023 IEEE 23RD INTERNATIONAL CONFERENCE ON NANOTECHNOLOGY, NANO
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
Anubha Sehgal, Kunal Kranti Das, Seema Dhull, Sourajeet Roy, Brajesh Kumar Kaushik
Summary: In this paper, an artificial neural network (ANN) based surrogate modeling is used to estimate the variability in multilevel SOT-MRAM. The results show that the ANN approach can quickly predict the impact of device parameter variations on resistance and write energy.
2023 IEEE 23RD INTERNATIONAL CONFERENCE ON NANOTECHNOLOGY, NANO
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
Alok Kumar Shukla, Hemkant Nehete, Partha Kaushik, Sandeep Soni, Brajesh Kumar Kaushik
Summary: Radiation-induced soft errors pose challenges to the reliability of conventional memories, but spintronic-based memories offer a potential solution with their non-volatility, high speed, and radiation tolerance. This paper introduces a machine learning-assisted approach to investigate radiation induced charges in radiation hardened MRAM circuits, providing accurate and efficient analysis of soft errors.
2023 IEEE 23RD INTERNATIONAL CONFERENCE ON NANOTECHNOLOGY, NANO
(2023)
