Article
Materials Science, Multidisciplinary
Jakub Jasinski, Akshay Balgarkashi, Valerio Piazza, Didem Dede, Alessandro Surrente, Michal Baranowski, Duncan K. Maude, Mitali Banerjee, Riccardo Frisenda, Andres Castellanos-Gomez, Anna Fontcuberta i Morral, Paulina Plochocka
Summary: Strain is a commonly used tool to tune optoelectronic properties, especially for TMDs. This paper presents a novel approach to induce strain in MoS2 monolayers using homoepitaxially grown GaAs nanomembranes, which allows for the integration of TMDs with III-V semiconductor nanostructures. The strain lifts the degeneracy of exciton states, resulting in linearly polarized emission with the polarization axis determined by the orientation of the nanomembranes.
Article
Engineering, Electrical & Electronic
Andrey B. Pashkovskii, Sergey A. Bogdanov, Askhat K. Bakarov, Alexandr B. Grigorenko, K. S. Zhuravlev, Vladimir G. Lapin, Vladimir M. Lukashin, Ilya A. Rogachev, Evgeniy Tereshkin, Sergey Shcherbakov
Summary: In this article, a GaAs millimeter-wave pseudomorphic high-electron-mobility transistor (pHEMT) using sophisticated AlGaAs-InGaAs-GaAs heterostructure is presented, demonstrating high mobility and high density of two-dimensional electron gas. The transistor shows impressive RF characteristics with high specific output RF power.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Article
Chemistry, Physical
Nikola Papez, Rashid Dallaev, Pavel Kaspar, Dinara Sobola, Pavel Skarvada, Stefan Talu, Shikhgasan Ramazanov, Alois Nebojsa
Summary: This work focuses on the degradation of GaAs solar cells under continuous laser irradiation. The solar cells were exposed to intense light for two months, leading to changes in electrical characteristics and structural composition. Analysis using various techniques such as Raman spectroscopy and X-ray photoelectron spectroscopy confirmed displacement of titanium and aluminum atoms, as well as slight redistribution of oxygen bonds in the anti-corrosion coating.
Article
Chemistry, Multidisciplinary
Bo Wang, Liming Wang, Yichi Zhang, Maolong Yang, Dongdong Lin, Ningning Zhang, Zuimin Jiang, Maliang Liu, Zhangming Zhu, Huiyong Hu
Summary: This paper presents a 2D MoS2/3D Ge junction field-effect transistor with low subthreshold swing and high on/off ratio. The device exhibits bidirectional photoresponse and three controllable current states can be realized by changing the gate voltage and infrared light.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Multidisciplinary Sciences
Hugo Henck, Diego Mauro, Daniil Domaretskiy, Marc Philippi, Shahriar Memaran, Wenkai Zheng, Zhengguang Lu, Dmitry Shcherbakov, Chun Ning Lau, Dmitry Smirnov, Luis Balicas, Kenji Watanabe, Takashi Taniguchi, Vladimir Fal'ko, Ignacio Gutierrez-Lezama, Nicolas Ubrig, Alberto F. Morpurgo
Summary: This study demonstrates the realization of light-emitting field-effect transistors based on van der Waals heterostructures. The devices showed electrically tunable and material-dependent electroluminescence spectra at room temperature, making them promising for controlling the spectrum of emitted light. The study also proposes the use of atomically thin semiconductors as a platform for achieving large spectral changes in electroluminescence.
NATURE COMMUNICATIONS
(2022)
Article
Engineering, Electrical & Electronic
Ming Xu, Chun Liu, Wei Luo, Chengjie Wang, Jiahao Chang, Rujun Liu, Qian Liu, Wanli Jia, Guanghui Qu
Summary: The investigation of nonlinear transient characteristics of gallium arsenide (GaAs) photoconductive semiconductor switches (PCSS) is of great significance for its applications in pulsed power technology. In this study, the researchers employed a laser diode (LD) with an energy of 2 mu J to trigger the GaAs PCSS. They observed compressed pulse width and increased amplitude as the bias electric field increased. Numerical modeling revealed that these effects can be attributed to negative differential mobility (NDM) and electric-field screening (EFS). The compression of pulse width provides the potential for relieving heat accumulation and suppressing device failure for high-repetition-rate applications.
IEEE ELECTRON DEVICE LETTERS
(2022)
Article
Physics, Condensed Matter
Durgesh C. Tripathi, D. Ritter
Summary: The absence of traps and a back-barrier in an ideal GaN heterojunction field-effect transistor leads to significant performance degradation due to space charge limited current through the buffer layer. This effect results in current leakage in both short and long channel devices in the off state, and primarily determines the output resistance at saturation.
SOLID STATE COMMUNICATIONS
(2021)
Article
Engineering, Electrical & Electronic
Heng Xie, Yong Fan, Wang Yang Li, Lei Wang, Yu Jian Cheng
Summary: This letter presents a Ka-band watt-level high-efficiency Doherty power amplifier (DPA) monolithic microwave integrated circuit (MMIC) in 90-nm gallium arsenide (GaAs) pseudomorphic high-electron-mobility transistor (pHEMT) technology. The proposed DPA exhibits high efficiency at 6-dB power back-off (PBO) with a low-loss compact Doherty output network and optimized peaking amplifier design.
IEEE MICROWAVE AND WIRELESS TECHNOLOGY LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Liqiang Tian, Hongqi Wang, Dong Jing, Cong Pan, Wei Shi, Chao Zhang
Summary: The formation of avalanche charge domain in high-power GaAs devices has been numerically studied, showing that the peak electric field is mainly influenced by bias electric field, carrier concentration, and device length, while the domain width is primarily affected by carrier concentration and device length. Impact ionization of carriers and avalanche multiplication significantly impact the peak electric field and domain width, indicating a close relationship between their values and the position of the domain during motion. These findings contribute to a deeper understanding of GaAs device breakdown mechanisms and can help optimize device performance.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2021)
Review
Materials Science, Multidisciplinary
Masataka Higashiwaki
Summary: Beta-gallium oxide, with its large bandgap energy and ability to synthesize large-size single-crystal bulks, has gained attention in the past decade for its potential applications in next-generation power devices. Research on its material properties and growth technologies has become active worldwide, leading to the development of state-of-the-art diodes and transistors with promising future prospects.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2021)
Article
Multidisciplinary Sciences
Atsushi Tanaka, Ryuji Sugiura, Daisuke Kawaguchi, Yotaro Wani, Hirotaka Watanabe, Hadi Sena, Yuto Ando, Yoshio Honda, Yasunori Igasaki, Akio Wakejima, Yuji Ando, Hiroshi Amano
Summary: This study demonstrates a laser slicing technique for cutting GaN substrates and investigates its applicability in device fabrication. Thinning of GaN-on-GaN high-electron-mobility transistors (HEMTs) was successfully achieved using this technique, with no significant adverse effects observed on the structural and electrical properties of the devices. The laser slicing process can be applied after device fabrication, offering a new approach to fabricating thin devices with reduced consumption of GaN substrates.
SCIENTIFIC REPORTS
(2022)
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
Automation & Control Systems
Hui Xiao, Huaiqing Zhang, Wei Song, Jiapeng Wang, Weihao Chen, Mingyu Lu
Summary: This article presents a high-input power rectifier circuit for 2.45-GHz microwave wireless power transmission, which is designed based on a GaAs FET and a Schottky diode. The novel design achieves a higher input power range and MW-dc power conversion efficiency, with a maximum conversion efficiency of 74.42% at 30 dBm input power. The circuit can operate efficiently with varying input power levels and load values, demonstrating the potential for providing power to electronic devices with different impedance.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2022)
Article
Multidisciplinary Sciences
Goutham Arutchelvan, Quentin Smets, Devin Verreck, Zubair Ahmed, Abhinav Gaur, Surajit Sutar, Julien Jussot, Benjamin Groven, Marc Heyns, Dennis Lin, Inge Asselberghs, Iuliana Radu
Summary: Two-dimensional semiconducting materials, such as MoS2, show promising performance for ultimate device scaling, with excellent transconductance and subthreshold swing. The study reveals that scaling the top-contact length does not affect the contact resistance and electrostatics in three monolayers MoS2 transistors, due to dominant edge injection. Furthermore, short channel lengths lead to subthreshold swing degradation, which can be mitigated by reducing the capacitive effective oxide thickness and lowering the Schottky barrier height.
SCIENTIFIC REPORTS
(2021)
Article
Physics, Applied
Praneeth Ranga, Arkka Bhattacharyya, Adrian Chmielewski, Saurav Roy, Rujun Sun, Michael A. Scarpulla, Nasim Alem, Sriram Krishnamoorthy
Summary: This study reports on the growth and characterization of metalorganic vapor-phase epitaxy-grown beta-(AlxGa1-x)(2)O-3/beta-Ga2O3 modulation-doped heterostructures. An electron channel is achieved in the heterostructure by utilizing a delta-doped beta-(AlxGa1-x)(2)O-3 barrier, with characteristics studied using various measurement methods. The fabricated transistor demonstrates high peak current and on-off ratio, while the electron channel in beta-(AlxGa1-x)(2)O-3 displays promising charge density and mobility at room temperature.
APPLIED PHYSICS EXPRESS
(2021)
Article
Nanoscience & Nanotechnology
Xuefei Li, Zhiyang Wang, Ke Chen, Dmitry Y. Zemlyanov, Liyan You, Jianguo Mei
Summary: The development of a nanostructured, amorphous vanadium oxide (VOx) ion-storage material that matches the electroactive voltage windows with the paired electrochromic polymers significantly improves the cycling stability of solid-state electrochromic devices. This leads to the creation of high-performance magenta-to-transmissive hybrid electrochromic devices that can be reversibly switched for 50,000 cycles with less than 5% optical loss.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Medicinal
Sonal Bhujbal, Vaibhav Pathak, Dmitry Y. Zemlyanov, Lynne S. Taylor, Qi (Tony) Zhou
Summary: This study developed amorphous solid dispersion (ASD) of lumefantrine using a cost-effective spray anti-solvent precipitation method, studying four acidic polymers as excipients at different drug-polymer ratios. The results showed that HPMCP and HPMCAS-based ASDs exhibited the best physical stability and drug release levels.
JOURNAL OF PHARMACEUTICAL SCIENCES
(2021)
Article
Nanoscience & Nanotechnology
Junxian Gao, Kaustubh J. Sawant, Jeffrey T. Miller, Zhenhua Zeng, Dmitry Zemlyanov, Jeffrey P. Greeley
Summary: The study investigated the interfacial interaction of well-defined ultrathin ZnOxHy films on Pd(111) under varying gas-phase conditions, revealing that zinc oxide, as an irreducible oxide, can spread on metal surfaces and show an SMSI-like behavior in the presence of hydrogen. A mixed canonical-grand canonical phase diagram was developed to bridge the gap between UHV conditions and true SMSI environments, revealing that certain ZnOxHy films with stoichiometries that do not exist in bulk are stabilized by Pd in the presence of hydrogen. This study proposes that SMSI metal nanoparticle encapsulation for irreducible oxide supports such as ZnO involves both surface (hydroxy)oxide and surface alloy formation, depending on the environmental conditions.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Medicine, Research & Experimental
Chailu Que, Alexandru Deac, Dmitry Y. Zemlyanov, QingQing Qi, Anura S. Indulkar, Yi Gao, Geoff G. Z. Zhang, Lynne S. Taylor
Summary: This study investigated the relationship between drug chemical structure and the limit of congruency (LoC) in PVPVA-based ASDs. Different types of drug-polymer interactions were found to impact the dissolution performance of ASDs, providing insights into the role of drug and polymer chemical structures on LoC and ASD performance in general.
MOLECULAR PHARMACEUTICS
(2021)
Article
Medicine, Research & Experimental
Tze Ning Hiew, Dmitry Y. Zemlyanov, Lynne S. Taylor
Summary: This study compares the solid-state stability and release performance of amorphous solid dispersions (ASDs) formulated with neutral and enteric polymers. The results show that ASDs formulated with enteric polymers have slower release rates of both the drug and polymer, and greater resistance to drug crystallization.
MOLECULAR PHARMACEUTICS
(2022)
Article
Chemistry, Physical
Philip M. Piper, Robert M. Orth, Dmitry Y. Zemlyanov, Timothee L. Pourpoint
Summary: The study investigates the formation mechanisms and structures of carbonaceous deposits in rocket engines using various spectroscopic techniques, revealing different formation processes for the carbon layers. Gas chromatography mass spectrometry and other methods were used to analyze the composition of the deposits.
Article
Materials Science, Multidisciplinary
John N. Hodul, Nikhil F. Carneiro, Allison K. Murray, Wilson Lee, Kelly M. Brayton, Xinping He, Carsten Flores-Hansen, Dmitry Zemlyanov, George T-C Chiu, James E. Braun, Bryan W. Boudouris, Jeffrey F. Rhoads
Summary: Formaldehyde, commonly found in construction materials, paints, and plastics, is harmful to health. Monitoring its presence indoors is crucial for public health. Researchers have developed a low-cost, small-scale, selective, and sensitive indoor sensor capable of real-time formaldehyde detection. They found that poly(5-carboxyindole) (P5C), an easily synthesized polymer, has rapid response times to formaldehyde gas at low concentrations. Blending P5C with beta-cyclodextrin (BCD) further enhances its response to formaldehyde gas and provides chemically selective adsorption.
JOURNAL OF MATERIALS SCIENCE
(2022)
Article
Chemistry, Physical
Cory A. Milligan, Ranga Rohit Seemakurthi, Junxian Gao, Jeffrey P. Greeley, Jeffrey T. Miller, Fabio H. Ribeiro, Dmitry Y. Zemlyanov
Summary: This study investigates the structure and reaction mechanism of PdZn catalysts using experimental and computational methods. The experimental results show that PdZn alloy surfaces have lower adsorption capacity for CO and propylene, and propylene cannot adsorb on the alloy surface, thereby inhibiting deeper reactions. This provides theoretical evidence for the capture of CO intermediates in alkene dehydrogenation reactions.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Vaibhav Pathak, Heejun Park, Dmitry Zemlyanov, Sonal Bhujbal, Maizbha Uddin Ahmed, Mohammad A. K. Azad, Jian Li, Qi Tony Zhou
Summary: The purpose of this study was to prepare pulmonary powder formulations containing both colistin and tobramycin and evaluate their in vitro aerosol performance and storage stability. The results showed that the 1:1 and 1:5 combination formulations exhibited higher fine particle fractions and better storage stability, possibly due to the enrichment of colistin on the co-spray dried particle surface.
PHARMACEUTICAL RESEARCH
(2022)
Article
Physics, Applied
Jie Zhang, Adam Charnas, Zehao Lin, Dongqi Zheng, Zhuocheng Zhang, Pai-Ying Liao, Dmitry Zemlyanov, Peide D. Ye
Summary: This Letter reports the improvement of electrical performance in indium oxide thin film transistors through a low-temperature CF4/N2O plasma treatment. The study finds that fluorination via CF4/N2O plasma effectively reduces excessive electrons in the In2O3 channel, resulting in improved electrical properties such as higher mobility, more positive threshold voltage, higher on/off current ratio, smaller subthreshold swing, and increased stability to gate biases. X-ray photoelectron spectroscopy confirms the fluorine incorporation and its role in enhancing TFT performance.
APPLIED PHYSICS LETTERS
(2022)
Article
Chemistry, Medicinal
Ruochen Yang, Geoff G. Z. Zhang, Dmitry Y. Zemlyanov, Hitesh S. Purohit, Lynne S. Taylor
Summary: Formulating poorly soluble molecules as amorphous solid dispersions (ASDs) is an effective strategy to improve drug release, but the release rate diminishes with increasing drug loading. The study investigated the connection between phase separation and release properties in ritonavir (RTV)-polyvinylpyrrolidone/vinyl acetate (PVPVA) ASDs. It was found that discrete drug-rich droplets at lower drug loadings led to rapid release, while a continuous drug-rich phase at higher drug loadings caused poor release.
JOURNAL OF PHARMACEUTICAL SCIENCES
(2023)
Article
Chemistry, Analytical
Ziyi Cao, Dustin M. Harmon, Ruochen Yang, Aleksandr Razumtcev, Minghe Li, Mark S. Carlsen, Andreas C. Geiger, Dmitry Zemlyanov, Alex M. Sherman, Nita Takanti, Jiayue Rong, Yechan Hwang, Lynne S. Taylor, Garth J. Simpson
Summary: The use of periodically structured illumination coupled with spatial Fourier-transform fluorescence recovery after photobleaching (FT-FRAP) allows for diffusivity mapping within segmented domains of arbitrary shape. By encoding spatial maps of diffusion onto harmonic peaks in the spatial Fourier transform, diffusion imaging by FT-FRAP improves signal to noise ratio and simplifies mathematical analysis. This technique has been applied to map spatially resolved diffusion differences within phase-separated domains of model amorphous solid dispersion spin-cast thin films, with implications for the design of stable storage and efficient delivery of therapeutic molecules.
ANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Medicinal
Tze Ning Hiew, Sugandha Saboo, Dmitry Y. Zemlyanov, Ashish Punia, Michael Wang, Daniel Smith, Michael Lowinger, Marina A. Solomos, Luke Schenck, Lynne S. Taylor
Summary: Co-precipitation is examined as a novel manufacturing approach for amorphous solid dispersions (ASDs) and its impact on processing conditions, surface composition, and release performance is evaluated. Hierarchical particles with an additional water soluble component coating the surfaces of core ASD particles were successfully created. It was found that cPAD particles with lower surface drug concentration exhibited improved release compared to particles with higher surface drug concentration.
JOURNAL OF PHARMACEUTICAL SCIENCES
(2023)
Article
Chemistry, Analytical
Ziyi Cao, Dustin M. Harmon, Ruochen Yang, Aleksandr Razumtcev, Minghe Li, Mark S. Carlsen, Andreas C. Geiger, Dmitry Zemlyanov, Alex M. Sherman, Nita Takanti, Jiayue Rong, Yechan Hwang, Lynne S. Taylor, Garth J. Simpson
Summary: The use of periodically structured illumination coupled with spatial Fourier-transform fluorescence recovery after photobleaching (FT-FRAP) enables diffusivity mapping within segmented domains of arbitrary shape. Diffusion is encoded onto harmonic peaks in the spatial Fourier transform through periodic comb-bleach patterning of the excitation beam. Image segmentation prior to Fourier transformation enhances signal to noise ratio and supports pooling for regions of similar diffusivity. The results provide insights into the recovery kinetics within amorphous/amorphous phase-separated domains and have implications for the design of amorphous systems for therapeutic molecule delivery.
ANALYTICAL CHEMISTRY
(2023)
Article
Chemistry, Physical
Cory A. Milligan, Ranga Rohit Seemakurthi, Junxian Gao, Jeffrey P. Greeley, Jeffrey T. Miller, Fabio H. Ribeiro, Dmitry Y. Zemlyanov
Summary: This study investigates the structural properties and thermal stability of PdZn surface alloys on Pd(111) and Pd(100) single crystal substrates. The adsorption of CO and propylene on the PdZn surfaces is explored, and lower binding energies of CO and propylene on PdZn surfaces compared to Pd surfaces are observed. This study highlights the importance of propylene adsorption on PdZn alloy catalysts for alkane dehydrogenation.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
