Article
Engineering, Electrical & Electronic
Daniele Inserra, Guangjun Wen
Summary: A compact and low-profile metal mountable tag device for UHF RFID applications is designed using a PIFA structure. The tag structure includes three lumped elements and a U-shaped slot for post-manufacturing tuning, making it possible to easily restore the design working frequency.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2021)
Article
Computer Science, Information Systems
Yuanxun Ethan Wang
Summary: This article presents a general theory on the noise matching performance of receivers with electrically small antennas (ESAs) in HF and VHF applications through theoretical analyses, discussions, and circuit simulations. The theory considers all noise sources and their interplay, as well as the impact from the physical constraint of the ESA and scaling of transistor technology. The noise performance of two receiver examples, one with an electrically small dipole and the other with an electrically small loop, is evaluated using full-wave simulations, and the results are compared to the theory.
Article
Computer Science, Information Systems
Amjaad T. T. Altakhaineh, Saqer S. S. Alja'afreh, Aser M. M. Almatarneh, Eqab Almajali, Luae Al-Tarawneh, Jawad Yousaf
Summary: This study presents a new design for an ultra-compact shared-aperture antenna using a quarter-mode substrate integrated waveguide (QMSIW) cavity. The antenna operates as a 4x4 MIMO system in three 5G/6G mmWave bands and as a single element antenna in a 5.5 GHz Wi-Fi Microwave band. It achieves quad-band operation and exhibits favorable characteristics, making it suitable for various wireless communication systems.
Article
Chemistry, Analytical
Bashar Bahaa Qas Elias, Ping Jack Soh
Summary: This work presents an efficient design and optimization method based on characteristic mode analysis (CMA) to predict the resonance and gain of wideband antennas made from flexible materials. Two compact, flexible planar monopole antennas designed on different materials and two different feeding methods are presented and analyzed to demonstrate the effectiveness of the method. The optimized results from the method are in agreement with the results from full wave simulations.
Article
Chemistry, Physical
Aparna Srilakshmi Praturi, Dai-Sik Kim, Bhanu Pratap Singh, Parinda Vasa
Summary: Metal nanostructures supporting plasmonic resonances play a crucial role in enhancing light harvesting for solar energy conversion. Optimizing the structural and spectral parameters of emitter-metal nanostructure hybrid systems is essential for maximizing conversion efficiency. Results show that hybrid systems can significantly enhance excitation rates and suppress luminescence, making them ideal for photovoltaic and photocatalysis applications. Nanostructures with a higher aspect ratio are found to be more efficient in this regard.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Engineering, Electrical & Electronic
Daniele Inserra, Guangjun Wen
Summary: This paper presents a dual-orthogonal-port stacked annular ring microstrip patch antenna for polarization diversity applications and full-duplex communications, utilizing vertical pins for port coupling cancellation and achieving high isolation performance, suitable for simultaneous transmit and receive applications.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2021)
Article
Engineering, Electrical & Electronic
Hui Li, Jinbo Yu, Yunze Diao, Kexin Liu
Summary: This article proposes a method to design multiband and multiport terminal antennas using the N-port characteristic mode approach, and illustrates the design procedure with examples of handset and vehicular antennas.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Maxim Neradovskiy, Herve Tronche, Dmitry Chezganov, Elena Pashnina, Evgeniy Vlasov, Pascal Baldi, Tommaso Lunghi, Vladimir Shur, Florent Doutre, Marc De Micheli
Summary: This paper proposes an alternative technique based on the characterization of the second harmonic generation signature of a nonlinear waveguide, which can be used to study the refractive index profile of waveguides, including the high-order spatial modes, which are important for probing the distribution of waveguides.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Alexander J. Angilella, Nichole K. Davis, Ian T. McMichael
Summary: This study explores the use of piezocomposite materials for impedance matching in electrically small strain antennas and proposes a methodology for achieving impedance matching without the need for an external network. The study also reveals that the radiation resistance of piezoelectric strain antennas is much smaller than that of similarly sized electric dipole antennas.
IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
(2022)
Article
Nanoscience & Nanotechnology
Ruowei Yu, Caoyuan Wang, Fetah Benabid, Kin Seng Chiang, Limin Xiao
Summary: This paper explores the mechanism of robust mode matching for ultra-large mode-area photonic crystal fibers and standard single mode fibers, achieving record-low splice loss and improved mechanical strength. By using a new reverse tapering approach, precise matching between different types of fibers is achieved, overcoming the challenge of splicing dissimilar fibers.
Article
Geochemistry & Geophysics
Jiayuan Li, Wangyi Xu, Pengcheng Shi, Yongjun Zhang, Qingwu Hu
Summary: In this article, a simple but very effective multimodal feature matching algorithm called locally normalized image feature transform (LNIFT) is proposed. LNIFT reduces the nonlinear radiation distortion (NRD) between multimodal images by using a local normalization filter to convert original images into normalized images for feature detection and description. Experimental results show that LNIFT outperforms RIFT in terms of efficiency, success rate, and number of correct matches.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2022)
Article
Engineering, Electrical & Electronic
Kin-Lu Wong, Miao-Fang Jian, Ching-Jui Chen, Jian-Zhong Chen
Summary: A new two-port same-polarized rectangular patch antenna is proposed for MIMO access-point antenna application, which achieves good port isolation through simple probe feeds. A design example in a specific frequency band shows good impedance matching, port isolation, and antenna efficiency.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2021)
Article
Computer Science, Information Systems
Bernat Oller, Aurora Andujar, Jaume Anguera
Summary: The exponential growth in the number of internet-connected devices over the past decade has made IoT and global connectivity more feasible each year, leading to a wide range of applications. This necessitates the development of more efficient wireless devices, particularly with regards to antenna design for connectivity, range, and battery life. An antenna booster technology is proposed, utilizing a small component to induce currents in the IoT device's ground plane. This allows for a remarkably compact antenna booster measuring only 12 mm x 3 mm x 2.4 mm, approximately representing λ/30 at 863 MHz. The antenna booster is matched across the frequency range through a matching network. The paper compares the bandwidth of an antenna booster and a monopole antenna for a specific design, holding a ground plane size of 120 mm x 60 mm in the 863 MHz to 928 MHz frequency range. Subsequently, the same designs are evaluated for various ground plane sizes, ranging from 20 mm x 30 mm to 200 mm x 200 mm in 10 mm increments, to determine which approach can be reused with minimal changes to the antenna system. The results show that the antenna booster can be reused across 53.8% of the ground planes with S-11 < -6 dB, while the monopole antenna can only be reused across 4.6%. Additionally, the antenna booster demonstrates superior total efficiencies of up to 2.3 dB. A physical prototype incorporating the antenna booster validates the numerical analysis.
Article
Computer Science, Interdisciplinary Applications
Yi Chen, Changzhou Hua, Jun Xu, Yunlong Lu, Jifu Huang
Summary: An efficient tunable decoupling and matching method is proposed for simplifying compact mobile terminal antennas by operating simultaneously in two independent bands. The study systematically investigates multi-element antenna systems and demonstrates the design and performance validation of a two-element antenna system.
INTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING
(2021)
Article
Engineering, Electrical & Electronic
Geert Morthier, Gunther Roelkens, Roel Baets
Summary: This article compares the power efficiency of signal transmission over optical carrier and RF carrier. It reveals that in direct optical detection schemes, the noise equivalent power is significantly higher than that of RF signal detection with an antenna. RF transmission has an advantage over optical transmission when the available bandwidth is limited.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2022)
Article
Multidisciplinary Sciences
Ankan Bag, Martin Neugebauer, Uwe Mick, Silke Christiansen, Sebastian A. Schulz, Peter Banzer
NATURE COMMUNICATIONS
(2020)
Article
Nanoscience & Nanotechnology
Sebastian W. Schmitt, Klaus Schwarzburg, George Sarau, Silke H. Christiansen, Sven Wiesner, Catherine Dubourdieu
Article
Chemistry, Multidisciplinary
Nadine J. Schrenker, Zhuocheng Xie, Peter Schweizer, Marco Moninger, Felix Werner, Nicolas Karpstein, Mirza Makovic, George D. Spyropoulos, Manuela Goebelt, Silke Christiansen, Christoph J. Brabec, Erik Bitzek, Erdmann Spiecker
Summary: This study investigates the fundamental deformation modes of five-fold twinned AgNWs in anisotropic networks and observes the impact of network anisotropy on electrical performance. By using a scale-bridging microscopy approach, three fundamental deformation modes of NWs are identified, which can explain the behavior observed in the study.
Article
Nanoscience & Nanotechnology
Magdalena Sola-Garcia, Kelly W. Mauser, Matthias Liebtrau, Toon Coenen, Silke Christiansen, Sophie Meuret, Albert Polman
Summary: Photon bunching in incoherent cathodoluminescence spectroscopy results from the interaction of high-energy electrons with a material, generating multiple photons and revealing key properties of electron-matter excitation. An analytical model has been developed to describe the amplitude and shape of the second order autocorrelation function for continuous and pulsed electron beams, including ultrashort pulses. Experimental data on InGaN/GaN quantum wells show good agreement with the model, providing insights on excitation efficiencies and nonlinear effects.
Article
Nanoscience & Nanotechnology
Victor Deinhart, Lisa-Marie Kern, Jan N. Kirchhof, Sabrina Juergensen, Joris Sturm, Enno Krauss, Thorsten Feichtner, Sviatoslav Kovalchuk, Michael Schneider, Dieter Engel, Bastian Pfau, Bert Hecht, Kirill Bolotin, Stephanie Reich, Katja Hoeflich
Summary: Focused beams of helium ions are powerful in machining with high precision. However, achieving such precision over large areas and different materials is challenging. The Python toolbox FIB-o-mat provides automated pattern creation and optimization, with high-level pattern creation and low-level beam path creation capabilities. Three applications demonstrate the potential of He ion beam nanofabrication for two-dimensional material systems and devices.
BEILSTEIN JOURNAL OF NANOTECHNOLOGY
(2021)
Article
Nanoscience & Nanotechnology
Philipp Grimm, Gary Razinskas, Jer-Shing Huang, Bert Hecht
Summary: The study demonstrates that a generalized version of coherent perfect absorption (gCPA) can be applied to nanoresonators with radiative losses, offering the possibility of achieving perfect impedance matching between different components in plasmonic systems.
Article
Physics, Multidisciplinary
Alexander Stegmaier, Stefan Imhof, Tobias Helbig, Tobias Hoefmann, Ching Hua Lee, Mark Kremer, Alexander Fritzsche, Thorsten Feichtner, Sebastian Klembt, Sven Hofling, Igor Boettcher, Ion Cosma Fulga, Libo Ma, Oliver G. Schmidt, Martin Greiter, Tobias Kiessling, Alexander Szameit, Ronny Thomale
Summary: Using electric circuit networks, we studied topological states of matter in non-Hermitian systems with parity-time symmetry and chiral symmetry. The impact of PT-symmetric gain and loss on localized edge and defect states was analyzed, revealing distinct properties of topological edge states and defect states. Our findings provide insights into future routes for topological defect engineering and tuning in non-Hermitian systems of arbitrary dimension.
PHYSICAL REVIEW LETTERS
(2021)
Article
Materials Science, Multidisciplinary
George Sarau, Christoph Daniel, Martin Heilmann, Gerd Leuchs, Kerstin Amann, Silke H. Christiansen
Summary: Graphene-based materials are increasingly utilized in novel nanomedicine technologies due to their large contact and loading surfaces as well as high sensitivities to chemical changes. The study on biomolecule-monolayer graphene-kidney tissue hybrid structures revealed a double-sided graphene-enhanced Raman scattering effect and efficient autofluorescence quenching caused by graphene on kidney tissue emissions. These phenomena can be explained by molecular structure and energy level alignment, leading to effective charge transfer.
ADVANCED MATERIALS TECHNOLOGIES
(2021)
Article
Optics
Korbinian J. Kaltenecker, Shreesha D. S. Rao, Mattias Rasmussen, Henrik B. Lassen, Edmund J. R. Kelleher, Enno Krauss, Bert Hecht, N. Asger Mortensen, Lars Gruener-Nielsen, Christos Markos, Ole Bang, Nicolas Stenger, Peter Uhd Jepsen
Summary: This study developed a low-noise supercontinuum (SC) source for high resolution, spectrally resolved near-field measurements in the near-infrared (NIR) region. The SC light source was used to demonstrate the first NIR, spectrally resolved s-SNOM measurement and characterize the dispersion curve of surface plasmon polariton (SPP) waves in the NIR, representing a technological breakthrough for potential new applications in near-field studies.
Article
Nanoscience & Nanotechnology
Xiaofei Wu, Raphael Ehehalt, Gary Razinskas, Thorsten Feichtner, Jin Qin, Bert Hecht
Summary: Researchers have successfully demonstrated the remote control of microscopic robots in two dimensions in all three degrees of freedom using unfocused light and plasmonic nanoantennas. This breakthrough has potential applications in transport, manipulation, and sensing of nano and mesoscale objects.
NATURE NANOTECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Kirill Gubanov, Manuel Johnson, Melda Akay, Benedikt C. C. Wolz, Dan Shen, Xing Cheng, Silke Christiansen, Rainer H. H. Fink
Summary: Advances in organic materials manufacturing have enabled the creation of electronic devices using solution-processing techniques. This study demonstrates the use of micro-contact for high-quality structured electrodes in top-contact organic field-effect transistors (OFETs) by depositing poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) polymer ink. The optimized solution-processing fabrication of OFETs shows promising potential for simple and cost-effective roll-to-roll manufacturing processes, with comparable electrical performance to transistors with gold electrodes and lower contact resistance (R-c) due to carbon-based organic electrodes.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Lamborghini Sotelo, Tommaso Fontanot, Sanjana Vig, Patrick Herre, Peyman Yousefi, Maria Helena Fernandes, George Sarau, Gerd Leuchs, Silke Christiansen
Summary: This study investigates the effect of the initial surface roughness of TiAl6V4 samples on laser-induced periodic surface structures (LIPSS), surface wettability, and chemistry. Different polishing grain sizes were used to adjust the surface roughness of the samples. Laser irradiation was performed with varying laser power and distance. The resulting structures were characterized by SEM, AFM, Raman spectroscopy, and contact angle measurements. The study also explores the bone implant viability of the generated structures. The results demonstrate that initial surface roughness affects the wettability and orientation of the resulting LIPSS, and structures with higher integrated fluence enhance cell differentiation and reduce bacterial activity, making them promising for bone implant compatibility and durability.
ADVANCED MATERIALS TECHNOLOGIES
(2023)
Article
Nanoscience & Nanotechnology
Lucia H. Prado, David Boehringer, Anca Mazare, Lamborghini Sotelo, George Sarau, Silke Christiansen, Ben Fabry, Patrik Schmuki, Sannakaisa Virtanen, Wolfgang H. Goldmann, Alexander B. Tesler
Summary: Researchers have developed a convenient UV-grafting technique to covalently attach silicone-based coatings to solid substrates. The short-time exposure to UV light results in the formation of lubricant-infused slippery surfaces (LISS), while longer exposure leads to the formation of semi-rigid cross-linked polydimethylsiloxane (PDMS) coatings. These coatings exhibit excellent resistance to corrosion and biofouling in aquatic environments. Due to its simple fabrication, low cost, rapid binding kinetics, eco-friendliness, non-toxicity to aquatic life, and excellent wetting-repellent characteristics, this technology has great potential for implementation in aquatic environments.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Computer Science, Interdisciplinary Applications
Benedikt Christopher Wolz, Christian Jaremenko, Florian Vollnhals, Lasse Kling, Jan Wrege, Silke Christiansen
Summary: Through silicon vias (TSVs) are a key enabling technology for interconnection and realization of complex three-dimensional integrated circuit (3D-IC) components. X-ray microscopy (XRM) is a rising method for analyzing the internal structure of samples without destructive sample preparation. However, there is a lack of evaluated scan recipes or best practices for studying TSVs using XRM. In recent years, there has been increased interest in automated machine learning and deep learning approaches for qualitative and quantitative inspection processes.
ENGINEERING REPORTS
(2022)
Article
Physics, Multidisciplinary
Tommaso Tufarelli, Daniel Friedrich, Heiko Gross, Joachim Hamm, Ortwin Hess, Bert Hecht
Summary: This study demonstrates a new method to enhance the coupling constant of a single quantum emitter by collectively coupling multiple nearly degenerate transitions of the emitter to the same field mode. The resulting effective Jaynes-Cummings model shows a boosted coupling constant of order root N, retaining quantum optical nonlinearities. The findings closely match recent experiments and will aid in controlling and detecting single-photon nonlinearities at ambient conditions.
PHYSICAL REVIEW RESEARCH
(2021)
