Article
Chemistry, Physical
Tomasz Andrearczyk, Janusz Sadowski, Jerzy Wrobel, Tadeusz Figielski, Tadeusz Wosinski
Summary: The study found that adding 1% Bi atoms to the (Ga,Mn)(Bi,As) epitaxial layers significantly enhances the strength of the planar Hall effect. Additionally, Bi incorporation into the layers enhances their coercive fields and uniaxial magneto-crystalline anisotropy. This material may have potential applications in spintronic devices.
Article
Chemistry, Multidisciplinary
Jeongchun Ryu, Can Onur Avci, Moojune Song, Mantao Huang, Ryan Thompson, Jiseok Yang, San Ko, Shutaro Karube, Nobuki Tezuka, Makoto Kohda, Kab-Jin Kim, Geoffrey S. D. Beach, Junsaku Nitta
Summary: Current-induced spin-orbit torques (SOTs) are used to control magnetic elements and non-uniform magnetic textures. This study reports a current-induced, external field-free switching of a trilayer structure with a large perpendicular anisotropy. The switching is driven by strong SOTs, local anisotropy fluctuations, and the Dzyaloshinkii-Moriya interaction inherent to the system.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Kosuke O. Hara, Ryota Takagaki, Keisuke Arimoto, Noritaka Usami
Summary: In this study, the microstructure and its effects on the electrical and optoelectronic properties of BaSi2 films grown by close-spaced evaporation were investigated. It was found that using Si(100) substrates, increasing film thickness and growth temperature can decrease the density of epitaxial domain boundaries, improve carrier lifetime, and enhance the performance of BaSi2 films for photovoltaic applications.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Engineering, Electrical & Electronic
T. Paulauskas, J. Devenson, S. Stanionyte, M. Skapas, V Karpus, B. Cechavicius, S. Tumenes, V Strazdiene, B. Sebeka, V Pacebutas
Summary: Molecular beam epitaxy growth and analysis of GaAsBi on compositional step-graded InGaAs buffer layers are presented in this study. The developed buffer is only 240 nm thick, exhibits very low surface roughness while reaching up to 0.46% lattice-mismatch with a GaAs substrate. Reciprocal-space mappings showed that 500 nm thick GaAsBi layers with 2.7%-5.3% Bi remain pseudomorphic with the InGaAs buffer, in contrast to GaAsBi grown on GaAs that were found to incur up to 50% lattice relaxation. CuPtB-type ordering and associated polarized photoluminescence were also found in the bismide layers grown on the InGaAs buffers. Optical anisotropy of a strain-free 2.7% Bi GaAsBi was further analysed by a suite of optical techniques indicating that the valence band splitting is similar to 40 meV. This study advances synthesis techniques of thick GaAsBi layers for optoelectronic device applications.
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2022)
Article
Physics, Condensed Matter
Omer Donmez, Mustafa Gunes, Mohamed Henini, Ayse Erol
Summary: The introduction of transition metals to conventional III-V semiconductors has anomalous effects on their fundamental characteristics, such as electronic, magnetic, and structural properties. This study demonstrates the use of the valence band anti-crossing (VBAC) model to calculate the electronic band structure of Ga0.97-xMn0.03CrxAs epitaxial layers. The interaction between localized Mn and Cr defect states and valence band states reconstructs and splits the valence bands, resulting in the formation of an impurity band and fundamental valence band edge.
PHYSICA B-CONDENSED MATTER
(2023)
Article
Nanoscience & Nanotechnology
Yang Chen, Haoming Wei, Yangqing Wu, Bingqiang Cao
Summary: This study manipulated the ferroelectric domain structure in BiFe1-xCoxO3 films by controlling the Co-doped concentration. The results showed that different domain structures have different effects on the bulk photovoltaic effect, with the 71 degrees domain structure exhibiting larger depolarization field and higher photoconductivity. Optimizing the domain structure can effectively enhance the bulk photovoltaic effect and provide a new method for regulating the domain structure in photovoltaic devices.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Chemistry, Inorganic & Nuclear
Mao-Yin Ran, Sheng-Hua Zhou, Wenbo Wei, Bang-Jun Song, Yong-Fang Shi, Xin-Tao Wu, Hua Lin, Qi-Long Zhu
Summary: In this study, two novel chalcohalides CdSnSX2 (X = Cl or Br) with unique two-dimensional neutral layers were successfully synthesized. These chalcohalides exhibit high visible-light-induced photocatalytic activity for rhodamine B degradation, showing a performance approximately 7.0 times higher than that of nitrogen-doped TiO2 under the same experimental conditions.
INORGANIC CHEMISTRY
(2021)
Article
Multidisciplinary Sciences
Oksana Yastrubchak, Nataliia Tataryn, Lukasz Gluba, Sergii Mamykin, Janusz Sadowski, Tomasz Andrearczyk, Jaroslaw Z. Domagala, Olga Kondratenko, Volodymyr Romanyuk, Olena Fedchenko, Yaryna Lytvynenko, Olena Tkach, Dmitry Vasilyev, Sergey Babenkov, Katerina Medjanik, Katarzyna Gas, Maciej Sawicki, Tadeusz Wosinski, Gerd Schoenhense, Hans-Joachim Elmers
Summary: The influence of adding Bi to dilute ferromagnetic semiconductor (Ga, Mn) As on its electronic structure, magnetic and structural properties was studied. The addition of Bi improved the structural perfection, magnetic properties, and hole concentration of the samples. It was found that the incorporation of Bi led to changes in the valence band and a shift in the spin-orbit split-off band to higher binding energies.
SCIENTIFIC REPORTS
(2023)
Article
Engineering, Electrical & Electronic
Borislav Hinkov, Hanh T. Hoang, Maxime Hugues, Jean-Michel Chaveau, Gottfried Strasser
Summary: Zinc oxide is a novel material system for mid-infrared and THz optoelectronics, with the non-polar m-plane orientation showing promise for device design. A new ICP-RIE process has been developed for etching m-Zn(Mg)O heterostructures, achieving smooth vertical sidewalls and high selectivity towards a SiN etch mask. Surface leakage currents in etched m-plane Zn(Mg)O structures can be significantly suppressed by treatment in hydrogen peroxide (H2O2).
SEMICONDUCTOR SCIENCE AND TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
R. Winkler, U. Zulicke
Summary: In this work, we use group theory to study electric, magnetic, and toroidal multipolar order in crystalline solids and identify five categories of polarized matter based on symmetry analysis. We also develop a general formalism of indicators for individual multipole densities. Our work provides a general framework for classifying and expanding current understanding of multipolar order in complex materials.
Article
Engineering, Electrical & Electronic
Chinedu Christian Ahia, Ngcali Tile, Edson L. Meyer, Johannes Reinhardt Botha
Summary: High resolution X-ray diffraction, scanning probe microscopy, scanning electron microscopy, and optical microscopy were used to evaluate the crystallinity and morphology of epitaxial layers of InSb deposited on GaSb substrate. The study showed that the thickness and quality of the deposited InSb layers are highly sensitive to changes in growth temperatures and V/III ratios, regardless of the Sb source used. Additionally, XRD patterns indicated an improvement in crystallinity for InSb layers deposited using TMSb compared to TDMASb.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2021)
Article
Physics, Condensed Matter
Monique Combescot, Shiue-Yuan Shiau
Summary: The angular momentum formalism provides a powerful way to classify atomic states, but it cannot be used for periodic systems due to the requirement of spherical symmetry. However, an analog of orbital angular momentum can be defined by only considering the potential felt by the electrons. The eigenvalues of (L) over cap and (J) over cap can be used as quantum indices to label cubic semiconductor states and control the phase factor.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Physics, Applied
Bhabani Prasad Sahu, Santosh Kumar Yadav, Simran Arora, Subhabrata Dhar
Summary: The incorporation of lithium in (111) NiO epitaxial layers grown using pulsed layer deposition technique on c-sapphire substrates has been studied. The effects of Li inclusion on the structural, morphological, electrical, and optical properties of the films were systematically investigated. It was observed that the concentration of Li in the film was higher at lower growth temperatures, but the crystalline quality decreased. There was a miscibility limit of Li in NiO, and Li clusters were detected in the films beyond a critical Li concentration. Li incorporation resulted in hydrostatic tensile strain in the NiO lattice, leading to a reduction in the bandgap and an improvement in the electrical conductivity of NiO layers. Ni-vacancy defects also played a significant role in controlling the conductivity of these samples.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Krzysztof Gawarecki, Pawel Scharoch, Michal Wisniewski, Jakub Ziembicki, Herbert S. Maczko, Marta Gladysiewicz, Robert Kudrawiec
Summary: In this paper, a ready-to-use symmetry-invariant expansion of the full-zone 30-band k.p Hamiltonian for the Td point group is derived. The parameters are found by calculating the band structures of III-V materials using a state-of-the-art DFT approach and adjusting the k.p bands to match the targets. Satisfactory agreement between the k . p model and the DFT band structures is achieved for all tested zinc-blende III-V semiconductors. The fitted k . p parameters are also compared with values calculated using momentum matrix elements obtained directly from DFT.
Article
Physics, Multidisciplinary
A. Khaliq, P. Dziawa, R. Minikaev, M. Arciszewska, A. Avdonin, B. Brodowska, L. Kilanski
Summary: IV-VI semiconductors possess multifunctional characteristics, such as topological surface states, ferroelectricity at room temperature, and giant Rashba spin-splitting, giving them the potential for next-generation spintronic applications. In this work, the structural and high field magnetotransport results of epitaxially grown α-GeTe and SnTe layers are presented, revealing their physical properties and behaviors.
ACTA PHYSICA POLONICA A
(2022)
Article
Chemistry, Multidisciplinary
Ali Imran, Muhammad Sulaman, Muhammad Yousaf, Muhammad Abid Anwar, Muhammad Qasim, Ghulam Dastgeer, Kossi A. A. Min-Dianey, Baoyu Wang, Xinqiang Wang
Summary: The demand for high mobility semiconductors has increased due to the fabrication of high-speed electronic and communication devices. Indium nitride (InN) could be a potential candidate for industrial applications due to its simple and low-cost fabrication process, as well as unique electronic properties such as narrow direct bandgap and high electron mobility. The experimental results demonstrate the high quality and high mobility of the InN film, making it a potential candidate for high-speed electronic/optoelectronic devices.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Tai Li, Wei Luo, Shangfeng Liu, Jiajia Yang, Renchun Tao, Ye Yuan, Zhaoying Chen, Jinlin Wang, Tao Wang, Xin Rong, Duo Li, Zhen Huang, Weiyun Wang, Junjie Kang, Xinqiang Wang
Summary: In this study, a substrate-dominated strain-modulation strategy was proposed to suppress the compressive strain in AlGaN-based UVB-LEDs, achieving outstanding performance with high LOP and stability.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Physics, Applied
Ian R. Berkman, Alexey Lyasota, Gabriele G. de Boo, John G. Bartholomew, Brett C. Johnson, Jeffrey C. McCallum, Bin-Bin Xu, Shouyi Xie, Rose L. Ahlefeldt, Matthew J. Sellars, Chunming Yin, Sven Rogge
Summary: We propose a flexible method for studying the optical properties of an Er3+ ensemble in Si through resonant excitation and in situ single-photon detection. This technique allows efficient detection of optically active centers in transparent crystals without nanofabrication. We observe 70 Er3+ resonances in Si, with 62 of them not previously observed, indicating the potential of Er3+ in Si as a quantum information candidate.
PHYSICAL REVIEW APPLIED
(2023)
Article
Chemistry, Physical
Yuji Zhao, Mingfei Xu, Xuanqi Huang, Justin Lebeau, Tao Li, Dawei Wang, Houqiang Fu, Kai Fu, Xinqiang Wang, Jingyu Lin, Hongxing Jiang
Summary: III-nitride InGaN material is an ideal candidate for high-performance photovoltaic solar cells, especially in high-temperature applications. This paper provides a comprehensive review of recent developments in InGaN-based solar cells, including theoretical modeling, material epitaxy, device engineering, and high-temperature measurement. Substrate technology and unique properties of InGaN materials, such as polarization control and positive thermal coefficient, are highlighted. Outstanding high-temperature InGaN-based solar cells with quantum efficiency approaching 80% at 450 degrees C have been demonstrated. Future innovations in epitaxy science, device engineering, and integration methods are required to further enhance the efficiency and expand the applications of InGaN-based solar cells.
MATERIALS TODAY ENERGY
(2023)
Article
Chemistry, Multidisciplinary
Zhaoying Chen, Bowen Sheng, Fang Liu, Shangfeng Liu, Duo Li, Zexing Yuan, Tao Wang, Xin Rong, Jingsheng Huang, Jiangying Qiu, Wenji Liang, Chunlei Zhao, Long Yan, Jason Hu, Shiping Guo, Weikun Ge, Bo Shen, Xinqiang Wang
Summary: High-performance InGaN red LEDs on sapphire grown by strain modulation and metal-organic chemical vapor deposition are reported, enabling the realization of high-resolution full-color mini/micro-LED displays.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Physics, Applied
Baoqing Zhang, Liuyun Yang, Ding Wang, Kai Cheng, Bowen Sheng, Zhiwen Liang, Ye Yuan, Bo Shen, Xinqiang Wang
Summary: Planar AlN/GaN resonant tunneling diodes (RTDs) are fabricated using a nitrogen ion implantation isolation process on silicon substrates. The active area of these RTDs is defined by nitrogen ion implantation. The planar RTD consists of two different-sized RTDs connected in series, and its performance is determined by the smaller one. The RTD exhibits stable negative differential resistance (NDR) and can be used for the design of GaN-based RTDs and monolithic microwave integrated circuits on large-size silicon wafers.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Applied
Liubing Wang, Fujun Xu, Jing Lang, Jiaming Wang, Lisheng Zhang, Xuzhou Fang, Ziyao Zhang, Xueqi Guo, Chen Ji, Xiangning Kang, Ning Tang, Xinqiang Wang, Zhixin Qin, Weikun Ge, Bo Shen
Summary: We aim to enhance the light extraction efficiency of AlGaN-based deep ultraviolet light-emitting diodes (DUV-LEDs) by introducing a highly transparent p-type layer and reflective Rh/Al p-type electrodes. The thinned p-GaN contact layer balances Ohmic contact and DUV light transmittance, enabling the Rh/Al p-type electrodes to exhibit high reflection and good electrical performance. After optimization, the Rh/Al reflective p-type electrodes achieve a reflectance greater than 70% and a specific contact resistivity of 3.75 x 10(-4) omega center dot cm(2). This improvement leads to a 57% increase in the highest wall-plug efficiency of 278 nm DUV-LEDs compared to the conventional configuration with Ni/Au p-type electrodes.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Physical
Jiaming Wang, Nan Xie, Fujun Xu, Lisheng Zhang, Jing Lang, Xiangning Kang, Zhixin Qin, Xuelin Yang, Ning Tang, Xinqiang Wang, Weikun Ge, Bo Shen
Summary: We propose a method to achieve high-quality III-nitride heteroepitaxial films by controlling the discretization and coalescence of columns. By using nano-patterned AlN/sapphire templates, discrete AlN columns coalesce with uniform orientations, effectively suppressing the regeneration of threading dislocations. The resulting AlN heteroepitaxial film shows a density of dislocation etch pits close to that of bulk single crystals.
Article
Physics, Applied
Zidong Cai, Xuelin Yang, Zhaohua Shen, Cheng Ma, Zhenghao Chen, Danshuo Liu, Fujun Xu, Ning Tang, Xinqiang Wang, Weikun Ge, Bo Shen
Summary: A carbon-regulated Si substrate can reduce the RF loss of GaN-based HEMT buffer stacks by suppressing the formation of parasitic conductive channel. By combining the substrate engineering with low-temperature growth, the RF loss of the buffer stacks can be reduced to 0.13 dB/mm at 10 GHz without degrading the crystal quality. This work demonstrates the potential for fabricating high-quality and low-loss GaN-on-Si RF devices.
APPLIED PHYSICS LETTERS
(2023)
Review
Optics
Xiaoyu Yang, Li Ma, Maotao Yu, Hao-Hsin Chen, Yongqiang Ji, An Hu, Qixuan Zhong, Xiaohan Jia, Yanju Wang, Yuzhuo Zhang, Rui Zhu, Xinqiang Wang, Changjun Lu
Summary: This paper focuses on the lagging progress of blue perovskite light-emitting diodes (PeLEDs) compared to their red and green counterparts. Recent advances and noteworthy strategies in optimizing microstructures, energy landscapes, and charge behaviors of wide-bandgap perovskite emitters are systematically reviewed. The stability of blue perovskite emitters and related devices is also discussed. In the end, a technical roadmap for fabricating state-of-the-art blue PeLEDs is proposed.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Review
Chemistry, Multidisciplinary
Valentin Jmerik, Vladimir Kozlovsky, Xinqiang Wang
Summary: This review focuses on UVC emitters with electron-beam pumping of heterostructures with quantum wells in an (Al,Ga)N material system. The advantages of these emitters include the absence of p-type doping and the ability to achieve high-output optical power values in the UVC range. The review discusses the world experience in implementing various UV emitters and pays special attention to the production of heterostructures with multiple quantum wells/two-dimensional quantum disks of GaN/AlN.
Article
Multidisciplinary Sciences
Fang Liu, Tao Wang, Xin Gao, Huaiyuan Yang, Zhihong Zhang, Yucheng Guo, Ye Yuan, Zhen Huang, Jilin Tang, Bowen Sheng, Zhaoying Chen, Kaihui Liu, Bo Shen, Xin-Zheng Li, Hailin Peng, Xinqiang Wang
Summary: Transferred graphene is a promising platform for fabricating multifunctional devices beyond the limitations of conventional substrates. The preferred epitaxy for single-crystal III-nitrides on wet-transferred graphene is quasi-vdWe, as demonstrated by inhibiting lattice inversion and resulting in a single-crystal film. This work is essential for the development of III-nitride semiconductor devices on two-dimensional materials such as graphene.
Article
Physics, Condensed Matter
Teng Fan, Ning Tang, Jiaqi Wei, Shixiong Zhang, Zhenhao Sun, Guoping Li, Jiayang Jiang, Lei Fu, Yunfan Zhang, Ye Yuan, Xin Rong, Weikun Ge, Xinqiang Wang, Bo Shen
Summary: The effects of annealing in an oxygen atmosphere on beta-Ga2O3 epilayers were studied using X-ray photoelectron spectroscopy, photoluminescence, and Fourier-transform infrared spectroscopy. The results showed that as the annealing temperature increased, the proportions of Ga3+ and O-L (lattice oxygen) increased, indicating the reduction of V-O defects. The changes in photoluminescence emissions indicated improved crystal quality and a decrease in V-O(1), V-O(2), and V-Ga defects. The annealing process led to the filling of V-O and V-Ga defects with oxygen and gallium atoms, primarily attributed to the bonding structures of Ga(1)-O(1) and Ga(1)-O(2) in GaO4 tetrahedra. These findings provide detailed information and guidelines for reducing intrinsic point defects in beta-Ga2O3.
MICRO AND NANOSTRUCTURES
(2023)
Article
Materials Science, Multidisciplinary
Zhen Huang, Renchun Tao, Duo Li, Zexing Yuan, Shanshan Sheng, Tao Wang, Tai Li, Zhaoying Chen, Ye Yuan, Junjie Kang, Zhiwen Liang, Qi Wang, Pengfei Tian, Bo Shen, Xinqiang Wang
Summary: In order to improve the performance of GaN-based green micro-light emitting diodes (mu-LEDs) array, a modular-architected p-type region is proposed, which consists of polarization-induced graded AlGaN and Al0.2Ga0.8N/GaN superlattices (SLs) to enhance p-type conductivity. The designed p-type structure exhibits a high hole concentration and excellent conductivity. The fabricated mu-LEDs array shows improved resistance, light output power, and data rate in comparison to devices with different p-type layers.
ADVANCED PHOTONICS RESEARCH
(2023)
Article
Materials Science, Multidisciplinary
Yong He, Jing Lu, Xinqiang Wang, Jun-jie Shi
Summary: This article proposes a design strategy for achieving superconductivity at ambient pressure by constructing few-hydrogen metal-bonded perovskite hydrides, such as Al4H, to address the challenge of high-pressure sample preparation. It predicts that Al4H has a favorable critical temperature Tc of up to 54 K under ambient pressure.
