Article
Materials Science, Multidisciplinary
Jingwei Zhang, Yuchao Wang, Rongguo Song, Zongkui Kou, Daping He
Summary: In this study, two wireless energy harvesting devices based on highly flexible graphene macroscopic films (FGMF) were designed, fabricated, and tested. The FGMFs-based rectifying circuit (GRC) demonstrated good flexibility and RF-to-DC efficiency of 53% at 2.1 GHz. Flexible wideband monopole rectenna and a 2.45 GHz wearable rectenna were also developed using FGMFs, with maximum conversion efficiencies of 52%, 46%, and 44% at different frequencies. These highly flexible graphene-film-based rectennas show great potential as wireless power suppliers for smart IoT applications.
ENERGY & ENVIRONMENTAL MATERIALS
(2022)
Article
Chemistry, Analytical
Bartlomiej Nowacki, Jakub Jala, Krystian Mistewicz, Roman Przylucki, Grzegorz Kopec, Tomasz Stenzel
Summary: The dynamic development of flexible wearable electronics has opened up new possibilities for the production and use of new types of sensors. Polymer nanocomposites have become increasingly popular in sensor fabrication due to their mechanical advantages and functional properties. This study presents the first fabrication of an SbSI/PU nanocomposite as a piezoelectric nanogenerator for strain detection, using simple and efficient technology. The nanocomposite exhibits high flexibility and durability, with a lack of defects in the material structure and low agglomeration of nanowires. The developed nanocomposite shows promising potential for energy harvesting from human body movement, such as being introduced into shoe soles.
Review
Chemistry, Multidisciplinary
Seong Dae Kim, Arijit Sarkar, Jong-Hyun Ahn
Summary: With the popularity of flexible and wearable electronic devices, research on lightweight and large-capacity batteries suitable for powering such devices is actively conducted. Graphene has attracted attention in the battery field due to its good mechanical properties and applicability in fabricating electrodes. Different types of graphene enable the fabrication of flexible and stretchable batteries with various shapes and functions.
Article
Chemistry, Physical
Hui Yu, Nan Li, Ni Zhao
Summary: The review investigates whether current flexible energy devices can meet the energy demand of wireless flexible sensor systems in long-term health monitoring applications. It estimates the total energy demand of typical sensor systems and discusses the design of the energy supply architecture. Health monitoring protocols that could be realized with self-powered system designs are suggested, and core challenges for further development of the technologies for practical applications are identified.
ADVANCED ENERGY MATERIALS
(2021)
Article
Computer Science, Information Systems
Juan-Manuel Lopez-Garde, Ruben Del-Rio-Ruiz, Jon Legarda, Hendrik Rogier
Summary: This paper presents a purely textile 2 x 2 rectenna array for RF energy harvesting, fostering research in wireless energy transmission for e-textiles. Utilizing the electromagnetically coupled microstrip patch antenna topology and a simple construction method, it provides good performance repeatability. Measurements in a real WiFi scenario were performed, showing feasibility for feeding e-textiles.
Article
Thermodynamics
Kangqi Fan, Pengwei Xia, Rongchun Li, Jiyuan Guo, Qinxue Tan, Danmei Wei
Summary: This paper presents a novel strategy for achieving high-performance energy harvesting backpacks by utilizing a flexible mechanical motion rectifier (MMR) to convert human motion-induced vibrations into high output power.
ENERGY CONVERSION AND MANAGEMENT
(2022)
Article
Computer Science, Information Systems
Giovanni Collodi, Monica Righini, Marco Passafiume, Alessandro Cidronali
Summary: This paper presents a compact batteryless node architecture suitable for backscattering communication. The node integrates a patch antenna with a non-50 Omega optimal port impedance, optimizing the wireless power conversion efficiency. Experimental results show a significant improvement in energy harvesting performance for the optimized node.
Article
Engineering, Electrical & Electronic
E. S. Kadir, R. N. Gayen
Summary: The study compared the mechanical energy harvesting properties of highly flexible, stretchable, and free-standing poly(vinylidene fluoride) (PVDF) membranes loaded with various nanofillers like zinc oxide (ZnO), graphene oxide (GO), and ZnO/GO composites. Composite polymer membranes with dominating beta-crystalline phase were synthesized using a simpler and low-cost chemical method. The mechanical to electrical energy conversion was observed by applying repetitive mechanical stress in different modes to the composite membranes.
SENSORS AND ACTUATORS A-PHYSICAL
(2022)
Article
Engineering, Electrical & Electronic
C. S. Boopathi, M. Sivaram, T. V. P. Sundararajan, R. Maheswar, P. Yupapin, Iraj S. Amiri
Summary: The proposed flexible bandenna utilizes a silicone wristband as the substrate, operating in the 2.45 GHz ISM band with stable directional radiation and gain greater than 5 dBi. It can be used as an ambient radio frequency energy harvester and integrated into future flexible electronic devices to support wireless communication.
MICROSYSTEM TECHNOLOGIES-MICRO-AND NANOSYSTEMS-INFORMATION STORAGE AND PROCESSING SYSTEMS
(2021)
Article
Chemistry, Multidisciplinary
Xiulei Qi, Lei Yu, Yide Liu, Long Chen, Xiankai Li
Summary: This study presents a bimetallic ion chelation strategy to produce liquid metal powders wrapped with a robust shell. These powders exhibit high chemical stability and superior photothermal effects, making them suitable for flexible electronics, smart actuators, and electric skins.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Mamina Sahoo, Sz-Nian Lai, Jyh-Ming Wu, Ming-Chung Wu, Chao-Sung Lai
Summary: This study successfully developed a novel multilayer graphene-based TENG, achieving a significant increase in charge density by introducing a charge trapping layer, resulting in a substantial improvement in output power and device stability. The TENG was able to power up to 20 green LEDs and provide sufficient power for an electronic timer, providing a new insight for energy harvesting in next-generation flexible electronics.
Article
Engineering, Electrical & Electronic
Zhen Li, Jing-Wei Zhang, Yu-Chao Wang, Da-Ping He, Cheng Zhang
Summary: A two-port rectenna is proposed for harvesting ambient RF power from five commercial bands. It achieves high power conversion efficiency at various frequencies by using a hybrid half-wave rectifier and two back-to-back slot antennas. The rectifier consists of a series and parallel branch, which allows it to cover multiple frequency bands with only one diode. The experimental results demonstrate its competitive performance in terms of band coverage and efficiency, indicating significant potential for RF energy harvesting and low-power applications.
IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS
(2023)
Review
Chemistry, Multidisciplinary
So-Yoon Yang, Vitor Sencadas, Siheng Sean You, Neil Zi-Xun Jia, Shriya Sruthi Srinivasan, Hen-Wei Huang, Abdelsalam Elrefaey Ahmed, Jia Ying Liang, Giovanni Traverso
Summary: The article reviews the state-of-the-art of powering technologies for implantable and ingestible biomedical electronics, highlighting the importance of developing safe, compact, and high volumetric energy density power sources for long-term in-body biomedical electronics and personalized healthcare. It also discusses novel batteries, energy harvesting devices, and energy transfer methods suitable for implantable and ingestible electronics.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Engineering, Electrical & Electronic
Fatma M. Abdel Hamied, Korany R. Mahmoud, Mohamed Hussein, Salah S. A. Obayya
Summary: In this paper, a nano-antenna design coupled to a rectifier diode is proposed for harvesting solar energy. The use of a multi-insulator structure in the rectifier diode enhances the responsivity and asymmetry. The proposed designs achieve high radiation efficiency and total harvesting efficiency.
OPTICAL AND QUANTUM ELECTRONICS
(2022)
Article
Chemistry, Multidisciplinary
Beibei Fan, Zhaozheng Wang, Guoxu Liu, Zheng Wang, Xianpeng Fu, Likun Gong, Chi Zhang
Summary: A robust flexible textile tribovoltaic nanogenerator based on a 2D dynamic heterojunction of 2H-MoS2/Ta4C3 has been developed. During the friction process, an electric field is generated and a significant number of electron-hole pairs are excited to generate direct current through the dynamic heterojunction. The output power density and robustness of the nanogenerator are investigated.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
M. Asad, S. Majdi, A. Vorobiev, K. Jeppson, J. Isberg, J. Stake
Summary: Graphene field-effect transistors (GFETs) operating at high frequencies show improved performance when using a diamond substrate, which allows for higher oscillation frequencies and efficient heat dissipation. GFET-on-diamond technology has the potential to achieve sub-terahertz frequency performance.
IEEE ELECTRON DEVICE LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Isabel Harrysson Rodrigues, Andrei Vorobiev
Summary: In this study, the carrier velocity in InGaAs/InP high-electron mobility transistors (HEMTs) was investigated using geometrical magnetoresistance. The results showed an opposite dependence between the low-field mobility and peak velocity. These findings are crucial for the development of advanced applications of HEMTs.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Physics, Applied
Isabel Harrysson Rodrigues, Andrey Generalov, Miika Soikkeli, Anton Murros, Sanna Arpiainen, Andrei Vorobiev
Summary: Further development of graphene field-effect transistors (GFETs) for high-frequency electronics requires accurate evaluation and study of the mobility of charge carriers in a specific device. This study demonstrates that the mobility in the GFETs can be directly characterized and studied using the geometrical magnetoresistance (gMR) effect. The gMR mobility is typically 2-3 times higher than that found via the commonly used drain resistance model.
APPLIED PHYSICS LETTERS
(2022)
Article
Engineering, Chemical
Marlene Bonmann, Diana Carolina Guio-Perez, Tomas Bryllert, David Pallares, Martin Seemann, Filip Johnsson, Jan Stake
Summary: This paper presents the development and validation of a sub-millimeter wave range-Doppler radar for non-intrusive sensing of solids concentrations in gas-solids systems. The radar system offers the ability to penetrate opaque materials, measure local solids velocity, and provide reflected radar power with high spatial resolution. The experimental results demonstrate that the radar system provides reliable measurements of solids concentrations with high accuracy.
ADVANCED POWDER TECHNOLOGY
(2023)
Article
Pharmacology & Pharmacy
Anis Moradikouchi, Anders Sparen, Olof Svensson, Staffan Folestad, Jan Stake, Helena Rodilla
Summary: In this study, the feasibility of using terahertz spectroscopy combined with multivariate analysis for the quantification of API concentration and tablet density in pharmaceutical tablets was explored. The results showed that terahertz spectroscopy can accurately measure tablet density and has lower scattering effects compared to Raman and NIR spectroscopy.
INTERNATIONAL JOURNAL OF PHARMACEUTICS
(2023)
Article
Physics, Applied
Isabel Harrysson Rodrigues, Niklas Rorsman, Andrei Vorobiev
Summary: To optimize graphene field-effect transistors (GFETs) for high-frequency applications, it is necessary to understand the physical mechanisms of charge carrier transport at short channel lengths. By using a quasi-ballistic transport model, we found that the carrier mobility decreases by more than half as the gate length decreases. This decrease is attributed to the impact of ballistic charge carrier transport.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Engineering, Electrical & Electronic
Juan Cabello-Sanchez, Vladimir Drakinskiy, Jan Stake, Helena Rodilla
Summary: Planar Goubau lines show promise for terahertz (THz) applications, but existing filters lack clear design procedures. In this study, we propose a design for a bandpass/bandstop filter by periodically loading the line with capacitively-coupled lambda/2 resonators. The filter's working principle is explained using a transmission-line model. We fabricated and tested a passband filter centered at 0.9 THz on a 10-µm silicon-membrane substrate, demonstrating good agreement between measurements and simulations.
IEEE TRANSACTIONS ON TERAHERTZ SCIENCE AND TECHNOLOGY
(2023)
Article
Optics
R. Voigt, M. Wienold, D. Jayasankar, V. Drakinskiy, J. Stake, P. Sobis, L. Schrottke, X. Lu, H. T. Grahn, H-W Huebers
Summary: We demonstrate the frequency stabilization of a terahertz quantum-cascade laser (QCL) using the Lamb dip of a D2O rotational transition absorption line. A Schottky diode harmonic mixer is used to generate a downconverted QCL signal, which is measured by a spectrum analyzer and shows a full width at half maximum of 350 kHz limited by high-frequency noise beyond the stabilization loop bandwidth.
Article
Physics, Applied
S. Majdi, V. Djurberg, M. Asad, A. Aitkulova, N. Suntornwipat, J. Stake, J. Isberg
Summary: In this study, the researchers successfully fabricated graphene-diamond heterostructures by transferring graphene to an ultra-pure single-crystalline diamond substrate. Hall-effect measurements were conducted to investigate the charge transport properties in these devices. Enhanced hole mobility of 2750 cm(2) V-1 s(-1) was observed at room temperature when using diamond with reduced nitrogen impurity concentration, and the upper limit for mobility was determined by electrostatically varying the carrier concentration. These results are promising for enabling room-temperature applications of carbon-carbon devices.
APPLIED PHYSICS LETTERS
(2023)
Article
Energy & Fuels
Diana Carolina Guio-Perez, Marlene Bonmann, Tomas Bryllert, Martin Seemann, Jan Stake, Filip Johnsson, David Pallares
Summary: The aim of this work is to demonstrate the value of radar technology for studying experimentally the solids flows in gas-solids fluidized beds. The work presents original results regarding the solids concentration and velocity acquired in a non-intrusive manner from a cold flow model. The radar technique applied in this work is a promising technique for detailed characterization of the solids flow in fluidized beds, offering high spatial and temporal resolutions, allowing the determination of both solids velocity and concentration, and having a reasonably high penetration depth.
Article
Engineering, Electrical & Electronic
Tomas Bryllert, Marlene Bonmann, Jan Stake
Summary: This work presents a 340-GHz frequency-modulated continuous-wave (FMCW) pulse-Doppler radar based on a transceiver module with high output power and wide bandwidth. The radar system demonstrates high sensitivity and resolution in detecting and mapping both single particles and particle clouds at a 5-m distance. The ability to monitor particle dynamics is valuable in various industrial applications.
IEEE TRANSACTIONS ON TERAHERTZ SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Electrical & Electronic
Juan Cabello-Sanchez, Vladimir Drakinskiy, Jan Stake, Helena Rodilla
Summary: In this work, a termination for planar Goubau lines (PGLs) based on an exponentially tapered corrugated line is proposed to achieve broadband impedance-matched loads with small reflections. A 400 μm-long PGL load was fabricated on a 10 μm-thick silicon substrate, and the measured reflections were below -19 dB in the frequency range of 0.5-1.1 THz, indicating good agreement between simulations and measurements.
IEEE MICROWAVE AND WIRELESS TECHNOLOGY LETTERS
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
Divya Jayasankar, Vladimir Drakinskiy, Peter Sobis, Jan Stake
Summary: This paper presents the design and sensitivity analysis of a 4.7-THz fundamental mixer operating at ambient temperatures. The critical circuit parameters for mixer performance at supra-THz frequencies are identified, highlighting the progress towards a room-temperature heterodyne supra-terahertz receiver.
2022 47TH INTERNATIONAL CONFERENCE ON INFRARED, MILLIMETER AND TERAHERTZ WAVES (IRMMW-THZ 2022)
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Divya Jayasankar, A. I. Hernandez-Serrano, Rachel A. Hand, Jan Stake, Emma MacPherson
Summary: The study indicates that frequency-dependent properties of polyvinyl alcohol-based hydrogel phantoms are similar to human skin, showing promising prospects for being utilized as a skin equivalent.
2022 52ND EUROPEAN MICROWAVE CONFERENCE (EUMC)
(2022)
Article
Infectious Diseases
Elise Hyser, Drashti Antala, Harvey Friedman, Jonathan Stake
Summary: This article presents a case of an elderly female who underwent a workup for acute blood loss anemia and incidentally discovered abdominopelvic actinomycosis. The case exemplifies how actinomycosis can mimic the presentation of cancer, with risk factors including a history of ischemic colitis and lumbar laminectomy.
