Article
Materials Science, Multidisciplinary
Ivan B. Karomi
Summary: This study compared InAsP QD materials with the standard InP QD laser and found that InAsP QD had a higher strain field and deeper dot confinement. The breakdown of the Fermi-Dirac distribution at 150K for InAsP QD materials was also observed, indicating the potential of InAsP for ultrafast source generation.
Article
Physics, Multidisciplinary
Rahul Ghosh
Summary: In this paper, a new approach to studying the one-dimensional Dirac equation with a position-dependent mass is presented. By considering the Fermi velocity as a local variable, the structure of the coupled equations is explored and an interesting constraint is obtained, where the mass is the inverse square of the Fermi velocity. Several solvable systems are discussed, including the free particle, shifted harmonic oscillator, Coulomb and nonpolynomial potentials. In the context of supersymmetric quantum mechanics, the upper partner of the effective potential leads to a new form for the inverse quadratic functional choice of the Fermi velocity.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2022)
Article
Chemistry, Multidisciplinary
Zhenyu Wang, Zhanyang Hao, Yayun Yu, Yuan Wang, Shiv Kumar, Xiangnan Xie, Mingyu Tong, Ke Deng, Yu-Jie Hao, Xiao-Ming Ma, Ke Zhang, Cai Liu, Mingxiang Ma, Jiawei Mei, Guang Wang, Eike F. Schwier, Kenya Shimada, Fufang Xu, Chang Liu, Wen Huang, Jianfeng Wang, Tian Jiang, Chaoyu Chen
Summary: This study reports the realization of moire Dirac cones in a monolayer In2Se3/bilayer graphene heterostructure, showing direct observation of Fermi velocity reduction and suggesting strong In2Se3/graphene interlayer coupling.
ADVANCED MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Manuel Kober-Czerny, Silvia Genaro Motti, Philippe Holzhey, Bernard Wenger, Jongchul Lim, Laura Maria Herz, Henry James Snaith
Summary: The charge carrier transport properties in layered perovskites, specifically 2D perovskite PEA(2)PbI(4), were investigated. The study found that layered perovskites have higher long-range and short-range mobilities, indicating that polycrystalline thin films have single-crystal-like qualities.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Physical
Wencai Yi, Xingang Jiang, Zhixiu Wang, Tao Yang, Bingchao Yang, Xiaobing Liu
Summary: This study reports 44 new two-dimensional Dirac materials, named ABX(6) monolayers, which exhibit excellent stability and elastic properties. The materials show high Fermi velocities and large band gaps, making them suitable for high-speed electronic devices. Some monolayers with heavy atoms display topological edge states, indicating their potential use in dissipationless transport devices.
APPLIED SURFACE SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Long Cheng, Chenmu Zhang, Yuanyue Liu
Summary: This paper reviews the first-principles methods for calculating the intrinsic carrier mobility of 2D semiconductors and the progress in understanding the underlying physical factors governing the mobility. The study provides perspectives on further research directions.
COMPUTATIONAL MATERIALS SCIENCE
(2021)
Article
Engineering, Electrical & Electronic
F. E. Bergamaschi, T. A. Ribeiro, B. C. Paz, M. de Souza, S. Barraud, M. Casse, M. Vinet, O. Faynot, M. A. Pavanello
Summary: This work investigates the variation of carrier mobility in Omega-gate silicon-on-insulator (SOI) nanowire MOS transistors induced by substrate biasing. Experimental measurements and 3-D TCAD simulation are used for analysis. It is found that lower back bias levels result in mobility enhancement due to initial conduction through the Si-BOX interface. However, increasing back bias leads to worse scattering mechanisms and mobility degradation in the back channel, especially for devices with larger fin width. The use of back bias is more beneficial for mobility in short-channel devices.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2022)
Article
Chemistry, Physical
Fazel Shojaei, Bohayra Mortazavi
Summary: Graphdiyne nanomaterials are low density, highly porous carbon-based two-dimensional materials with promising application prospects in electronic and energy storage/conversion systems. Recent advances have led to the successful fabrication of large-area pyrenyl and pyrazinoquinoxaline graphdiyne nanosheets. Theoretical simulations revealed the stability, electronic, optical, and mechanical properties of these novel nanosheets, showing their high stretchability and potential for adsorption in a wide range of light. Overall, these findings introduce pyrenyl and pyrazinoquinoxaline graphyne/graphyne as promising candidates for designing novel nanoelectronics and energy storage/conversion systems.
APPLIED SURFACE SCIENCE
(2021)
Article
Engineering, Electrical & Electronic
Xiomara Ribero-Figueroa, Anibal Pacheco-Sanchez, Aida Mansouri, Pankaj Kumar, Omid Habibpour, Herbert Zirath, Roman Sordan, Francisco Pasadas, David Jimenez, Reydezel Torres-Torres
Summary: Graphene field-effect transistors show negligible transconductance in certain scenarios. This research analyzes the dependence of channel and parasitic series resistances on gate and drain biases by extracting S-parameters. The study also considers the lossy nature of gate capacitance in the model.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Article
Engineering, Electrical & Electronic
Jialing Zhou, Jianwei Zhang, Hui Huang, Ruichen Shang, Senlin Jin, Junwei Cao, Yuan Zhong, Jun Yu, Jing Chen
Summary: The solution-gated transistor biosensor based on polycrystalline SnO2 thin film fabricated through the thermal oxidizing of Sn layer exhibits high sensitivity and low operating voltage. The performance can be optimized by tuning the oxidation temperature and grain size.
IEEE SENSORS JOURNAL
(2023)
Article
Crystallography
Songang Peng, Jing Zhang, Zhi Jin, Dayong Zhang, Jingyuan Shi, Shuhua Wei
Summary: The top-gated graphene field effect transistor (GFET) with electric-field induced doping polarity conversion has been demonstrated. The polarity of channel conductance in GFET can be transition from p-type to n-type through altering the gate electric field scanning range. This study promises to produce the complementary p- and n-type GFET for logic applications.
Article
Physics, Multidisciplinary
V Jakubsky, K. Zelaya
Summary: This article introduces the use of the framework of supersymmetric transformations in the construction of coupled systems of Dirac fermions. By constructing the energy operator using the generators of the associated superalgebra, the coupled Dirac fermions acquire different Fermi velocities. The article discusses in detail the peculiar spectral properties of this new system and illustrates emergent phenomena like level crossing and generation of bound states in continuum through two explicit examples.
Article
Materials Science, Multidisciplinary
Shingo Kaneta-Takada, Yuki K. Wakabayashi, Yoshiharu Krockenberger, Toshihiro Nomura, Yoshimitsu Kohama, Sergey A. Nikolaev, Hena Das, Hiroshi Irie, Kosuke Takiguchi, Shinobu Ohya, Masaaki Tanaka, Yoshitaka Taniyasu, Hideki Yamamoto
Summary: We have demonstrated the presence of high-mobility two-dimensional carriers with quantum oscillations in magnetic Weyl semimetal SrRuO3 epitaxial films. The quantum oscillations possibly originate from the surface Fermi arcs, and the linear thickness dependence of the phase shift provides evidence for their non-trivial nature. Additionally, the material exhibits the chiral anomaly of the Weyl nodes at low temperatures and high magnetic fields, suggesting potential applications in topological oxide electronics.
NPJ QUANTUM MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Kookjin Lee, Yeonsu Kim, Doyoon Kim, Jaewoo Lee, Hyebin Lee, Min-Kyu Joo, Young-Hoon Cho, Jinwoo Shin, Hyunjin Ji, Gyu-Tae Kim
Summary: This study investigates the impact of hot carrier injection on Schottky contacts in multilayer WSe2 FETs and finds that hot carrier injection can significantly improve device performance, especially in terms of subthreshold swing and contact resistances.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Crystallography
Jichao Li, Songang Peng, Zhi Jin, He Tian, Ting Wang, Xueyang Peng
Summary: This study found that a vacuum environment can improve the electrical performance of back-gate MoS2 field effect transistors, such as the current ratio, carrier mobility, and subthreshold swing, and can effectively remove absorbed molecules.
Article
Chemistry, Multidisciplinary
Luke W. Smith, Jack O. Batey, Jack A. Alexander-Webber, Yu-Chiang Hsieh, Shin- Fung, Tom Albrow-Owen, Harvey E. Beere, Oliver J. Burton, Stephan Hofmann, David A. Ritchie, Michael Kelly, Tse-Ming Chen, Hannah J. Joyce, Charles G. Smith
Summary: This study investigates the insulating states in monolayer graphene grown by chemical vapor deposition (CVD) and wet transferred on Al2O3 without specialized fabrication techniques. The results show the existence of insulating properties and the opening of an energy gap induced by the magnetic field in a graphene device with a bottleneck. A locally high-quality region within the bottleneck dominates transport and causes the device to behave as an insulating tunnel junction. The use of wet transfer fabrication techniques and multiplexing demonstrates the convenience of these scalable and reasonably simple methods for finding high-quality devices for fundamental physics research and functional properties.
Article
Chemistry, Multidisciplinary
Teja Potocnik, Peter J. Christopher, Ralf Mouthaan, Tom Albrow-Owen, Oliver J. Burton, Chennupati Jagadish, Hark Hoe Tan, Timothy D. Wilkinson, Stephan Hofmann, Hannah J. Joyce, Jack A. Alexander-Webber
Summary: We present a high-throughput method for identifying and characterizing individual nanowires, and for designing electrode patterns with high alignment accuracy. Our method utilizes an optimized marker system called LithoTag, which allows for nanometer-scale position determination of nanostructures. By incorporating computer vision algorithms, we can obtain location and property data for individual nanowires. Experimental results demonstrate the effectiveness of this method in automating nanodevice processing and improving fabrication efficiency.
Article
Physics, Applied
Abdullah M. Zaman, Yuichi Saito, Yuezhen Lu, Farhan Nur Kholid, Nikita W. Almond, Oliver J. Burton, Jack Alexander-Webber, Stephan Hofmann, Thomas Mitchell, Jonathan D. P. Griffiths, Harvey E. Beere, David A. Ritchie, Rostislav V. Mikhaylovskiy, Riccardo Degl'Innocenti
Summary: This study reports on the ultrafast modulation of a graphene loaded artificial metasurface on a SiO2/Si substrate, which was detected at the resonant frequency of approximately 0.8 THz using a terahertz probe. The results demonstrate that the sub-ps conductivity rising time is attributed to the combined effect of ultrafast generation of hot carriers in graphene and electron-hole generation in silicon. Furthermore, the study reveals the different recovery times of carrier-phonon relaxation in graphene and silicon, setting an upper limit for the reconfiguration speed achievable by graphene-based terahertz devices.
APPLIED PHYSICS LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Muhammad Zulqurnain, Oliver J. Burton, Mohamed Al-Hada, Lucy E. Goff, Stephan Hofmann, Louise C. Hirst
Summary: Remote epitaxy is an emerging technique for synthesizing low defect single crystal films using a 2D interface layer. This study demonstrates the growth of single crystal GaAs film by introducing defects in a graphene interface layer and employing molecular beam epitaxy.
Article
Physics, Applied
Xinhe Wang, Wei Yang, Wang Yang, Yuan Cao, Xiaoyang Lin, Guodong Wei, Haichang Lu, Peizhe Tang, Weisheng Zhao
Summary: This study found that spin flipping can be achieved by the valley-Zeeman spin-orbit field in monolayer WSe2 at room temperature, resulting in negative magnetoresistance in the vertical spin valve. Quantum transmission calculations confirmed the precessional spin transport of carriers under the giant spin-orbit field. Furthermore, the spin dynamics induced by the valley-Zeeman spin-orbit field was demonstrated to be tunable with the layer number and stacking phase of WSe2 as well as the gate voltage, providing a novel strategy for spin manipulation.
APPLIED PHYSICS REVIEWS
(2022)
Article
Chemistry, Multidisciplinary
Oliver J. Burton, Zachary Winter, Kenji Watanabe, Takashi Taniguchi, Bernd Beschoten, Christoph Stampfer, Stephan Hofmann
Summary: We introduce a fast-screening descriptor approach to achieve holistic optimization of the graphene-Cu model system and successfully prepare high-quality graphene with a very high yield. Our approach is adaptable to other descriptors and 2D material systems.
Review
Physics, Applied
J. Robertson, H. Naganuma, H. Lu
Summary: Magnetic tunnel junctions with MgO/Fe interfaces and perpendicular spin directions are widely used in spin-transfer torque magnetic random-access memories. The future scaling of MTJs may affect materials choices, including comparing 2D h-BN materials with existing MgO tunnel barriers. The effects of different h-BN interfacial sites on Ni or Co are compared in terms of their magnetoresistance, magnetic isotropy, and the pillow effect, balanced against the favorable chemical thermodynamics of the existing MgO barriers and MgO/Fe interfaces.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2023)
Article
Nanoscience & Nanotechnology
A. Gumprich, J. Liedtke, S. Beck, I Chirca, T. Potocnik, J. A. Alexander-Webber, S. Hofmann, S. Tappertzhofen
Summary: The fabrication and characterization of steep slope transistor devices based on low-dimensional materials require precise control over electrostatic doping profiles. In this study, we present a versatile graphene heterostructure platform with three buried individually addressable gate electrodes. The platform facilitates analysis of electrostatic doping of low-dimensional materials for novel low-power transistor devices.
Article
Chemistry, Multidisciplinary
Patrik Gubeljak, Tianhui Xu, Lorenzo Pedrazzetti, Oliver J. Burton, Luca Magagnin, Stephan Hofmann, George G. Malliaras, Antonio Lombardo
Summary: This paper presents a novel sensor based on graphene coplanar waveguides and microfluidic channels for the identification of non-amplified DNA sequences and single-base mutations. The sensor demonstrates high sensitivity and the ability to generate multidimensional datasets for advanced data analysis, achieving accurate discrimination between different DNA sequences even in the presence of noise and low signal-to-noise ratios.
Proceedings Paper
Engineering, Biomedical
Patrik Gubeljak, Lorenzo Pedrazzetti, Oliver J. Burton, Luca Magagnin, Stephan Hofmann, George G. Malliaras, Antonio Lombardo
Summary: This paper presents an electrolytically gated broadband microwave sensor where atomically-thin graphene layers are integrated into coplanar waveguides and coupled with microfluidic channels. The interaction between a solution under test and the graphene surface causes material and concentration specific modifications of graphene's DC and AC conductivity. Our devices represent a new and accurate metrological tool for chemical and biological sensing.
2022 IEEE INTERNATIONAL SYMPOSIUM ON MEDICAL MEASUREMENTS AND APPLICATIONS (MEMEA 2022)
(2022)
Article
Computer Science, Information Systems
Danyoung Cha, Yeonsu Kang, Soobin Lee, Sungsik Lee
Summary: The paper introduces a geometric optimization rule for synaptic pass-transistors in low-power analog accelerators. Simulation results show that scaling based on this rule can reduce static power consumption while maintaining synaptic characteristics. However, this scaling may lead to increased noise power-spectral-density, affecting the performance of the accelerator in terms of classification accuracy.
Article
Chemistry, Physical
Marco Carlotti, Saurabh Soni, Andrii Kovalchuk, Sumit Kumar, Stephan Hofmann, Ryan C. Chiechi
Summary: This paper presents a simple model for comparing the degree of electronic coupling between molecules and electrodes across different large-area molecular junctions. The model demonstrates its generalizability by comparing various junctions and can predict the differences in charge transport and rectification mechanisms. It provides useful insights for the design of new molecular motifs by synthetic chemists.
ACS PHYSICAL CHEMISTRY AU
(2022)
