Article
Energy & Fuels
S. Catalan-Gomez, E. Martinez Castellano, M. Schwarz, M. Montes Bajo, L. Dorado Vargas, A. Gonzalo, A. Redondo-Cubero, A. Gallego Carro, A. Hierro, J. M. Ulloa
Summary: This study investigates the use of core-shell gallium nanoparticles as functional light scatterers on solar cells. By optimizing the nanoparticle size, the short-circuit current of the solar cells is significantly improved. The underlying physical mechanism is studied through optical measurements and simulations, and a method to reduce the plasmonic effect of the nanoparticles is demonstrated.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2024)
Article
Engineering, Electrical & Electronic
Michael S. Shur
Summary: The terahertz (THz) technology has wide applications, with Beyond 5G Wi-Fi and Internet of Things (IoT) as its expected killer applications. Plasmonic TeraFETs with feature sizes down to 3 nm could enable a dramatic expansion of these applications.
IEEE SENSORS JOURNAL
(2021)
Article
Engineering, Electrical & Electronic
Daniel M. Dryden, Kyle J. Liddy, Ahmad E. Islam, Jeremiah C. Williams, Dennis E. Walker, Nolan S. Hendricks, Neil A. Moser, Andrea Arias-Purdue, Nicholas P. Sepelak, Kursti DeLello, Kelson D. Chabak, Andrew J. Green
Summary: We demonstrate a passivated MESFET fabricated on (010) Si-doped beta-Ga2O3 with breakdown over 2.4 kV without field plates, high Power Figure of Merit (PFOM), and high estimated Huang's Material Figure of Merit (HMFOM), owing to low gate charge and high breakdown. MESFETs with 13 μm source-drain spacing and 75 nm channel exhibited a current density of 61 mA/mm, peak transconductance of 27 mS/mm, and on-resistance of 133 Ω•mm. The device showed a PFOM competitive with state-of-the-art beta-Ga2O3 devices and a record high estimated HMFOM for a beta-Ga2O3 device, competitive with commercial wide-band gap devices. This demonstrates high-performance beta-Ga2O3 devices as viable multi-kV high-voltage power switches.
IEEE ELECTRON DEVICE LETTERS
(2022)
Article
Chemistry, Analytical
Pierre Fehlen, Guillaume Thomas, Fernando Gonzalez-Posada, Julien Guise, Francesco Rusconi, Laurent Cerutti, Thierry Taliercio, Denis Spitzer
Summary: Chemical warfare agents, such as sarin, are highly lethal to humans and require sensitive and selective detection. Infrared absorption spectroscopy is a powerful technique, but the mismatch between infrared light wavelength and molecule absorption cross-section dimensions reduces sensitivity. To address this, a plasmonic sensor using III-V semiconductors InAsSb with nano-antennas and enhanced electric field was proposed. Experiments using a sarin simulant showed that the sensor successfully detected the molecule at low concentrations. This work demonstrates the application of III-V semiconductor plasmonics for gas sensing of complex molecules using surface-enhanced infrared absorption.
SENSORS AND ACTUATORS B-CHEMICAL
(2023)
Article
Chemistry, Multidisciplinary
Chun-Yu Li, Chi-Ching Liu, Wei-Chih Lai, Yung-Chiang Lan, Yun-Chorng Chang
Summary: The study demonstrates the ability to exclude thermal effects and detect non-thermal hot carriers generated by surface plasmons using an AlGaN/GaN transistor. This ultra-sensitive platform shows at least two orders of magnitude more sensitivity compared to previous reports, offering a new way to optimize plasmonic nanoantenna design in various applications.
Article
Chemistry, Multidisciplinary
Bilal Barut, Xavier Cantos-Roman, Justin Crabb, Chun-Pui Kwan, Ripudaman Dixit, Nargess Arabchigavkani, Shenchu Yin, Jubin Nathawat, Keke He, Michael D. Randle, Farah Vandrevala, Takeyoshi Sugaya, Erik Einarsson, Josep M. Jornet, Jonathan P. Bird, Gregory R. Aizin
Summary: This study presents an approach to generate on-chip THz signals using nanoscale transistors with specific structural asymmetry. The asymmetry supports plasma-wave amplification, leading to pronounced NDC. The researchers also demonstrate how this feature can persist at high temperatures. These findings are a significant step forward for the development of active components for THz electronics.
Article
Chemistry, Multidisciplinary
Waseem A. Hussain, Kyle N. Plunkett
Summary: New conjugated polymers containing dihexylanthradithiophene (DHADT) in the main chain were successfully synthesized by Stille, Sonogashira, and Yamamoto cross-coupling polymerization reactions. These polymers exhibit notable optical features and are suitable for use in organic field effect transistors.
Article
Materials Science, Multidisciplinary
Fuming Wu, Yixuan Liu, Jun Zhang, Xiangxiang Li, Hui Yang, Wenping Hu
Summary: In this study, high-mobility stretchable semiconducting blend films were prepared by blending a polymer semiconductor with an elastomer. The resulting blend films have low crystallinity and high aggregation degree, resulting in high stretchability and high mobility. The fully stretchable organic transistors exhibit high hole maximum mobilities at various strains and show high mechanical robustness during repeated stretching-releasing cycles.
SCIENCE CHINA-MATERIALS
(2023)
Review
Chemistry, Multidisciplinary
Yuqiu Lei, Peiyun Li, Yuting Zheng, Ting Lei
Summary: Organic electrochemical transistors (OECTs) have shown great potential in various applications due to their high transconductance, low operating voltages, and good biocompatibility. However, the development of n-type and ambipolar OECT materials has lagged behind, which has limited the advancement of OECT-based logic circuits.
MATERIALS CHEMISTRY FRONTIERS
(2023)
Article
Multidisciplinary Sciences
Mohammad Samizadeh Nikoo, Elison Matioli
Summary: The evolution of electronics has been based on downsizing devices, but this approach faces limitations in terms of materials' potential and miniaturization. Traditional devices face issues such as carrier injection through tunnelling junctions and high parasitic capacitances. Ultra-scaled devices have low power delivery due to high electric fields. A new concept of electronic metadevices manipulates radiofrequency fields to achieve extraordinary electronic properties, enabling devices with high cutoff frequencies, conductance, breakdown voltages, and switching speeds. This work paves the way for ultrafast semiconductor devices and bridges the gap between electronics and optics.
Review
Materials Science, Multidisciplinary
Peng Hu, Xuexia He, Hui Jiang
Summary: Organic semiconductors are attracting attention for their advantages such as low-temperature processing ability, low fabrication cost, and flexibility. Studying high charge carrier mobility organic semiconductors with a mobility higher than 10 cm(2) V-1 s(-1) is crucial for future commercial microelectronic applications. Progress in discovering novel organic molecules and improving device fabrication technology has led to some organic molecules breaking existing knowledge limitations and demonstrating very high mobilities.
Article
Engineering, Electrical & Electronic
Ping Ma, Xianliang Li, Yuchi Zhang, Le Han, Yan Xu
Summary: By synthesizing hierarchical spinel-type semiconductors MGa2O4 (M = Ni, Co) through a hydrothermal method and subsequent calcination, their gas sensing performances were systematically investigated, revealing that the TEA gas sensing properties are significantly influenced by M(II) ions in the spinel structure.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2021)
Article
Engineering, Electrical & Electronic
Niemat Moultif, Olivier Latry, Eric Joubert, Mohamed Ndiaye, Christian Moreau, Jean-Francois Goupy, Patrick Carton
Summary: This study examines the reliability of AlGaN/GaN high-electron-mobility transistors under RF stress, showing a stabilization of gate contact after aging test, but observing degradation in RF performances and dc parameters due to bulk traps caused by hot-electron effects between gate-source or gate-drain. The trap-related phenomena lead to reductions in drain current and RF output power, as well as transconductance degradation and pinch-off shift. Emission measurements reveal an uneven distribution of light and the presence of native traps associated with crystallographic defects like dislocations or impurities.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2021)
Article
Physics, Applied
Mithun Bhowmick, Haowen Xi, Bruno Ullrich
Summary: This article introduces a model that accurately fits the absorption saturation parameter linked to the effective electron density of states, allowing for the comparison of experimentally found absorption limits and their variations in compound semiconductors with theoretical expectations. This is crucial for certain optoelectronic device applications.
JOURNAL OF APPLIED PHYSICS
(2023)
Review
Energy & Fuels
Jiaying Chen, Youtian Mo, Chaoying Guo, Jiansen Guo, Bingshe Xu, Xi Deng, Quan Xue, Guoqiang Li
Summary: The combination of III-V compound semiconductor materials and organic semiconductor materials is a potential pathway to solve the problems of conventional doped p-n junction solar cells. This review presents the recent progress of organic-inorganic hybrid solar cells based on polymers and III-V semiconductors, including materials, devices, growth processes, patterning and etching processes, advanced device structure designs, and optimization pathways for efficiency enhancement. The future development of such hybrid cells is also discussed.
Review
Energy & Fuels
Omer Faruk Noyan, Muhammad Mahmudul Hasan, Nezih Pala
Summary: Climate change, primarily caused by greenhouse gas emissions from carbon-based fossil fuel consumption, is a major challenge for humanity. The Ukrainian crisis has further complicated the global energy and food situation. The transition to clean and zero-carbon renewable energy sources, such as hydrogen technologies integrated with other renewables, is crucial for achieving energy independence and long-term solutions.
Article
Engineering, Biomedical
Michael Shur, Outman Akouissi, Olivier Rizzo, Didier J. Colin, John M. Kolinski, Stephanie P. Lacour
Summary: The study proposes a simple fabrication and processing sequence to deliver brain-like hydrogel implants into the nervous tissue. Real-time monitoring of hydrogel re-swelling kinetics in vivo is achieved using microcomputed tomography, and the study reveals how implant geometry and mechanical interplay govern in vivo buckling. These findings provide important guidance for the engineering of biomimetic brain implants.
Article
Physics, Applied
V. Ryzhii, C. Tang, T. Otsuji, M. Ryzhii, V. Mitin, M. S. Shur
Summary: We evaluated THz detectors based on graphene channel (GC) and a floating metal gate (MG) separated from GC by a black-phosphorus (b-P) or black-arsenic (b-As) barrier layer (BL). The operation of these GC-FETs involves heating of the two-dimensional electron gas in GC by THz radiation, leading to thermionic emission of hot electrons from GC to MG. This results in variation of the floating gate potential, affecting the source-drain current. At THz radiation frequencies close to plasmonic resonance frequencies in the gated GC, the variation in source-drain current and detector responsivity can be resonantly large.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Physics, Condensed Matter
I. M. Moiseenko, V. V. Popov, D. Fateev
Summary: For the first time, we investigate the interaction between the waveguide modes of a graphene structure and freely propagating terahertz electromagnetic waves. We discover a new physical phenomenon where incident THz waves can resonate with the surface TE modes of the graphene waveguide due to their dispersions near the light cone. We study the dispersion, amplification, and lasing of the surface TE modes in a dielectric waveguide covered with biased graphene layers, as well as the amplification and lasing of THz waves through TE mode resonances.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Multidisciplinary Sciences
Ingrid Torres, Sadegh Mehdi Aghaei, Nezih Pala, Angelo Gaitas
Summary: Graphene and multilayer graphene (MLG) have versatile properties and wide applications, but their production is challenging. This paper explores metal-induced crystallization to synthesize MLG directly on metal films and insulating substrates at much lower temperatures. Raman spectroscopy confirms the MLG properties of the synthesized carbon structure. The presented tip-based approach offers a simpler fabrication solution for MLG by eliminating photolithographic and transfer steps.
SCIENTIFIC REPORTS
(2023)
Review
Chemistry, Analytical
Randy Matos, Nezih Pala
Summary: Phase-change materials (PCMs) and metal-insulator transition (MIT) materials have the unique ability to change their material phase through external excitations, resulting in changes to their electrical and optical properties. This review paper discusses the current state-of-the-art PCMs within the context of reconfigurable intelligent surfaces (RIS), including their material properties, performance metrics, and potential applications in both wireless RF and optical fields, highlighting their impact on the future of RIS.
Review
Physics, Applied
V. Ryzhii, C. Tang, T. Otsuji, M. Ryzhii, V. Mitin, M. S. Shur
Summary: This article analyzes the operation of terahertz (THz) bolometric detectors based on field-effect transistor (FET) structures with graphene channels (GCs) and black-phosphorus and black-arsenic gate barrier layers (BLs). The detectors utilize the heating of a two-dimensional electron gas (2DEG) by THz radiation, leading to the emission of hot electrons into the gate via the BL. The excitation of plasmonic oscillations in the GC by THz signals results in a resonant detector response and increased responsivity.
PHYSICAL REVIEW APPLIED
(2023)
Article
Nanoscience & Nanotechnology
Azmal Huda Chowdhury, Borzooye Jafarizadeh, Nezih Pala, Chunlei Wang
Summary: This study presents a capacitve pressure sensor based on tissue paper, which is simple to produce and cost-effective yet exhibits high linear sensitivity, making it ideal for detecting wrist arterial pulse waveforms.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Physics, Applied
Babak Nikoobakht, Yuqin Zong, Okan Koksal, Amit Agrawal, Christopher Montgomery, Jaime Rumsey, Jacob Leach, Michael Shur
Summary: In this study, we investigate the impact of the fin aspect ratio on the external quantum efficiency (EQE) and UV emission of AlGaN fin/p-GaN heterojunctions. With decreasing aspect ratio, the UV emission of the fins increases and EQE is enhanced by 7 times. This can be attributed to the conservation of the volume of the carrier depletion region within a fin.
APPLIED PHYSICS LETTERS
(2023)
Article
Biophysics
Azmal Huda Chowdhury, Borzooye Jafarizadeh, Amin Rabiei Baboukani, Nezih Pala, Chunlei Wang
Summary: The growing interest in flexible electronics for physiological monitoring, particularly using flexible pressure sensors for cardiovascular pulse waveforms monitoring, has potential applications in cuffless blood pressure measurement and early diagnosis of cardiovascular disease. High sensitivity, fast response time, good pressure resolution and a high signal-to-noise ratio are essential for effective pulse waveform detection.
BIOSENSORS & BIOELECTRONICS
(2023)
Article
Physics, Multidisciplinary
Yuhui Zhang, Michael Shur
Summary: We demonstrate that a periodic multi-grated-gate structure can be used in THz plasmonic FETs (TeraFETs) to enhance THz detection sensitivity. By introducing spatial non-uniformity through separated gate sections, regions with different carrier concentrations and velocities are created, resulting in harmonic behaviors. The frequency spectrum of the DC voltage response consists of enhanced and suppressed regions. In the enhanced region, the response voltage amplitude can be increased up to approximately 100% compared to a uniform channel device. The distribution pattern of these regions is directly related to the number of gate sections (N (s)). A mapping of response amplitude in an N (s)-frequency scale is created, which aids in distinguishing enhanced/suppressed regions and locating optimal operating parameters.
FRONTIERS IN PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Borzooye Jafarizadeh, Azmal Huda Chowdhury, Md Shariful Islam Sozal, Zhe Cheng, Nezih Pala, Chunlei Wang
Summary: This letter introduces a novel testing technique and hardware setup to evaluate wearable, flexible piezoresistive pressure sensors. The testbed can assess sensitivity and durability of the sensors, and can simulate various blood pressures and heart rates, making it a vital tool for validating sensors for wearable pulse wave monitoring.
IEEE SENSORS LETTERS
(2023)
Proceedings Paper
Engineering, Electrical & Electronic
Muhammad Mahmudul Hasan, Yuhiu Zhang, Nezih Pala, Michael Shur
Summary: p-diamond is a strong candidate for sub-THz and THz applications due to its favorable properties, such as large hole effective mass, high optical phonon energy, high momentum relaxation time, and high mobility. Recent research on p-diamond TeraFETs has shown their potential for sub-THz and THz radiation detection and transmission. N-diamond TeraFETs also hold promise for emerging terahertz applications. One of the main factors affecting plasma wave dampening in our study is the viscosity of the charge carrier medium in the channel.
2023 IEEE 16TH DALLAS CIRCUITS AND SYSTEMS CONFERENCE, DCAS
(2023)
Proceedings Paper
Engineering, Biomedical
Azmal Huda Chowdhury, Borzooye Jafarizadeh, Md Shariful Islam Sozal, Zhe Cheng, Nezih Pala, Chunlei Wang
Summary: Flexible piezoresistive pressure sensors have gained significant attention due to their exceptional performance. This study presents a low-cost fabrication method for flexible piezoresistive pressure sensors, capable of detecting tactile pressure.
2023 IEEE BIOSENSORS CONFERENCE, BIOSENSORS
(2023)
