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Mapping orthorhombic domains with geometrical phase analysis in rare-earth nickelate heterostructures APL Mater. (IF 6.1) Pub Date : 2024-03-15 Bernat Mundet, Marios Hadjimichael, Jennifer Fowlie, Lukas Korosec, Lucia Varbaro, Claribel Domínguez, Jean-Marc Triscone, Duncan T. L. Alexander
Most perovskite oxides belong to the Pbnm space group, composed of an anisotropic unit cell, A-site antipolar displacements, and oxygen octahedral tilts. Mapping the orientation of the orthorhombic unit cell in epitaxial heterostructures that consist of at least one Pbnm compound is often needed for understanding and controlling the different degrees of coupling established at their coherent interfaces
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Electronic and optical properties of disordered getchellite: A photoreflectance, optical absorption, photoemission, and theoretical investigation APL Mater. (IF 6.1) Pub Date : 2024-03-15 Agata Sabik, Miłosz Grodzicki, Maciej P. Polak, Sandeep Gorantla, Alicja Bachmatiuk, Robert Kudrawiec, Wojciech M. Linhart
In this work, the optoelectronic properties of the getchellite crystal, a layered semiconducting disordered alloy with the chemical formula AsSbS3, are probed by a combination of complementary spectroscopic techniques, i.e., x-ray photoelectron spectroscopy together with a photoreflectance and a transmission spectroscopy. The experimental results are supported by a calculation based on density functional
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Magnetic functionalization and catalytic behavior of magnetic nanoparticles during laser photochemical graphitization of polyimide APL Mater. (IF 6.1) Pub Date : 2024-03-15 Abhishek Sarkar, Ho-won Noh, Ikenna C. Nlebedim, Pranav Shrotriya
We report laser-assisted photochemical graphitization of polyimides (PIs) into functional magnetic nanocomposites using laser irradiation of PI in the presence of magnetite nanoparticles (MNPs). PI Kapton sheets covered with MNP were photochemically treated under ambient conditions using a picosecond pulsed laser (1064 nm) to obtain an electrically conductive material. Scanning electron microscopy
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Enhancement of localized superconductivity in BaFe2As2 films via Co-ion implantation APL Mater. (IF 6.1) Pub Date : 2024-03-14 Myeongjun Oh, Jongmin Lee, Woun Kang, Sanghan Lee, Younjung Jo
In this study, we present a novel approach to localized superconductivity induction in BaFe2As2 films via targeted implantation of cobalt (Co) ions. Primarily, our study focuses on the systematic distribution of Co ions and the subsequent evolution of superconducting properties in Co-ion-implanted BaFe2As2 films. Our observations show that Co-ion distribution in the films is congruent with the results
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Incident beam current impact on space-charge retention in electron dynamitron irradiated polymethyl methacrylate APL Mater. (IF 6.1) Pub Date : 2024-03-14 Kathryn M. Sturge, Noah Hoppis, Aneesh Anandanatarajan, Ariana M. Bussio, Bryson C. Clifford, Emily H. Frashure, Miriam E. Hiebert, James E. Krutzler, Timothy W. Koeth
Dielectric charging aboard spacecraft and satellites is a persistent and pressing issue in materials design and applications. This study investigated the effect of electron irradiation on charge trapping and leakage properties in polymethyl methacrylate, which is necessary for determining the maximum permissible fluence of radiation before the material is pushed beyond its breakdown threshold in charged
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Pillararene-based donor–acceptor complex for ferroelectric self-assembled supramolecular materials APL Mater. (IF 6.1) Pub Date : 2024-03-13 Shuai Cao, Leqian Song, Yangyang Zheng, Kim Truc Nguyen, Huacheng Zhang, Jie Han
The investigation of ferroelectric materials is an important aspect of condensed matter physics. Compared to the traditional inorganic ferroelectric ones, organic ferroelectric materials possess unique advantages, including light weight, scalability, flexibility, and solvent treatability. However, the study of organic ferroelectric materials is still in its infancy, especially from the view of supramolecular
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Rapid coating of polyamide, polyurea, and polythiourea on metal–organic framework surfaces APL Mater. (IF 6.1) Pub Date : 2024-03-12 Yunmei Huang, Anheng Qi, Siqi Li, Lu Tang, Yingbo Zhao, Tao Li
Well-defined metal–organic framework (MOF)@polymer core–shell composite particles with polyamide, polyurea, and polythiourea as the shell layer have been constructed for the first time using non-solvent-induced surface-aimed polymerization. This surface polymerization method utilizes non-solvent-induced phase separation to concentrate and direct monomers onto MOF particle surfaces, thus completing
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Redox-active cerium-based metal–organic layers coordinated on carbon nanotubes as materials for supercapacitors APL Mater. (IF 6.1) Pub Date : 2024-03-12 Kuan-Chu Wu, Meng-Dian Tsai, Chung-Huan Wu, Tzu-Hsien Yang, You-Liang Chen, Chung-Wei Kung
In this work, the redox-active, two-dimensional (2D), and highly dispersible metal–organic layers (MOLs) constructed from hexa-cerium(IV) clusters, CeBTB (BTB = 1,3,5-benzenetribenzoate), were directly coordinated onto the surface of carboxylic acid-functionalized multi-walled carbon nanotubes (CNTs) by utilizing a post-synthetically grafting approach. Nanocomposites with various MOL-to-CNT ratios
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Formation of oxygen vacancy at surfaces of ZnO by trimethylaluminum APL Mater. (IF 6.1) Pub Date : 2024-03-12 Hyobin Eom, Woojin Bae, Ju Young Sung, Ji Hyeon Choi, Kyun Seong Dae, Jae Hyuck Jang, Tae Joo Park, Sang Woon Lee, Bonggeun Shong
The two-dimensional electron gas (2DEG) is a group of electrons that can move freely in horizontal dimensions but are confined in the third direction. It has been reported that atomic layer deposition (ALD) of Al2O3 on various reducible n-type oxides can lead to the formation of 2DEG at the heterojunction interfaces, among which ZnO is known to provide promising properties. In this study, we have performed
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Physics based optical modeling of iron disulfide thin films APL Mater. (IF 6.1) Pub Date : 2024-03-12 Awais Zaka, Sabina Abdul Hadi, Pratibha Pal, Dayanand Kumar, Nazek El-Atab, Saeed Alhassan, Ammar Nayfeh
In this work, physics based optical modeling is carried out using iron disulfide thin films deposited by using a plasma-assisted, radio frequency-powered technique. Iron disulfide is a transition metal dichalcogenide material, exhibiting a variety of unique and excellent characteristics. Various characterization techniques are employed to examine the growth rate, film thickness, and behavior of as-grown
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Strength degradation of GFRP cross-ply laminates in hydrothermal conditions APL Mater. (IF 6.1) Pub Date : 2024-03-12 Wen Cheng, Yan Cao
The changes in mechanical properties of glass fiber reinforced plastic cross-ply laminates as a result of hydrothermal aging were studied theoretically. The composite specimens have been immersed in distilled water at 25, 40, and 70 °C for 60 days for aging testing. Based on Fick’s law and the Arrhenius theorem, the moisture absorption data under different environments was analyzed, and the method
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Gradient index metamaterials for broadband underwater sound absorption APL Mater. (IF 6.1) Pub Date : 2024-03-08 Xiao Pan, Xinsheng Fang, Xuewen Yin, Yan Li, Yongdong Pan, Yabin Jin
The underwater broadband anechoic coating is highly demanded in acoustic stealth for underwater vehicles. In this work, we propose a gradient index metamaterial for broadband underwater sound absorption, which is further experimentally validated under high pressure conditions. The gradient index metamaterial consisting of radius-varied cavities in rubber allows the sound waves to follow the objective
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Accurate evaluation method for HRS retention of VCM ReRAM APL Mater. (IF 6.1) Pub Date : 2024-03-08 N. Kopperberg, D. J. Wouters, R. Waser, S. Menzel, S. Wiefels
Long-term retention is one of the major challenges concerning the reliability of redox-based resistive switching random access memories based on the valence change mechanism (VCM). The stability of the programmed state has to be ensured over several years, leaving a sufficient read window between the states, which is even more challenging at large statistics. Thus, the underlying physical mechanisms
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Observation of maxon-like ultrasound in elastic metabeam APL Mater. (IF 6.1) Pub Date : 2024-03-07 Peng Zhang, Yunya Liu, Keping Zhang, Yuning Wu, Fei Chen, Yi Chen, Pai Wang, Xuan Zhu
We observe maxon-like dispersion of ultrasonic guided waves in elastic metamaterials consisting of a rectangular beam and an array of cylindrical resonators. The pillars act as asymmetric resonators that induce a strong modal hybridization. We experimentally observe the strongly localized maxon mode with zero group velocity. Our study also demonstrates a unique feature of the maxon with a down-shifting
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Pressure-induced emission enhancement: A review APL Mater. (IF 6.1) Pub Date : 2024-03-07 Boyu Zou, Yingxue Han, Zhihao Yang, Qinglin Wang, Guangyu Wang, Guozhao Zhang, Yinwei Li, Cailong Liu
The luminescent properties of some materials undergo significant changes under compression. High pressure generated by a diamond anvil cell (DAC) is often used as an external stimulus to explore the relationship between the structures and luminescent properties of materials, provide traceable color and structural changes, and quantify the environment in which the materials are located. Under high pressure
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Acoustic meta-stethoscope for cardiac auscultation APL Mater. (IF 6.1) Pub Date : 2024-03-06 Ruoxue Dai, Zhengji Chen, Jingjing Liu, Jing Yang, Bin Liang, Jian-Chun Cheng
Straight cylindrical stethoscopes serve as an important alternative to conventional stethoscopes, whose application in the treatment of infectious diseases might be limited by the use of protective clothing. Yet their miniaturization is challenging due to the long wavelength of low-frequency cardiac sounds. Here, we present and experimentally demonstrate an acoustic meta-stethoscope with subwavelength
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Effect of resonant acoustic powder mixing on delay time of W–KClO4–BaCrO4 mixtures APL Mater. (IF 6.1) Pub Date : 2024-03-06 Kyungmin Kwon, Seunghwan Ryu, Soyun Joo, Youngjoon Han, Donghyeon Baek, Moonsoo Park, Dongwon Kim, Seungbum Hong
This study investigates the impact of resonant acoustic powder mixing on the delay time of the W–KClO4–BaCrO4 (WKB) mixture and its potential implications for powder and material synthesis. Through thermal analysis, an inverse linear relationship was found between thermal conductivity and delay time, allowing us to use thermal conductivity as a reliable proxy for delay time. By comparing the thermal
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Structural study of nickelate based heterostructures APL Mater. (IF 6.1) Pub Date : 2024-03-05 Lucia Varbaro, Bernat Mundet, Subhadeep Bandyopadhyay, Claribel Domínguez, Jennifer Fowlie, Lukas Korosec, Chih-Ying Hsu, Duncan T. L. Alexander, Philippe Ghosez, Jean-Marc Triscone
Heterostructures consisting of SmNiO3 and NdNiO3 alternating layers with additional LaAlO3 spacer layers were grown and fully characterized by means of x-ray diffraction, atomic force microscopy, and scanning transmission electron microscopy. A change in the orientation of the orthorhombic long-axis of the nickelate layers is observed when a single unit cell of LaAlO3 is inserted between SmNiO3 and
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High-mobility spin-polarized quasi-two-dimensional electron gas and large low-field magnetoresistance at the interface of EuTiO3/SrTiO3 (110) heterostructures APL Mater. (IF 6.1) Pub Date : 2024-03-05 Zhao-Cai Wang, Zheng-Nan Li, Mao Ye, Weiyao Zhao, Ren-Kui Zheng
High-mobility spin-polarized two-dimensional electron gas (2DEG) at the interfaces of complex oxide heterostructures provide great potential for spintronic device applications. Unfortunately, the interfacial ferromagnetism and its associated spin polarization of mobile electrons and negative magnetoresistance (MR) are too weak. As of now, obtaining enhanced interfacial ferromagnetism and MR and strong
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Area-selective deposition of germanium on patterned graphene/monolayer molybdenum disulfide stacks via dipole engineering APL Mater. (IF 6.1) Pub Date : 2024-03-05 Yeonjoo Lee, Towfiq Ahmed, Xuejing Wang, Michael T. Pettes, Yeonhoo Kim, Jeongwon Park, Woo Seok Yang, Kibum Kang, Young Joon Hong, Soyeong Kwon, Jinkyoung Yoo
Heterogeneous integration of two-dimensional materials and the conventional semiconductor has opened opportunities for next-generation semiconductor devices and their processing. Heterogeneous integration has been studied for economical manufacturing by substrate recycling and novel functionalities by a combination of incommensurate materials. However, utilizing the integration requires controlling
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Dielectric multilayers impact on radiation-induced charge accumulation in highly sensitive oxide field effect transistors APL Mater. (IF 6.1) Pub Date : 2024-03-05 Camilla Bordoni, Andrea Ciavatti, Mariana Cortinhal, Maria Pereira, Tobias Cramer, Pedro Barquinha, Beatrice Fraboni
Radiation dosimetry is crucial in many fields where the exposure to ionizing radiation must be precisely controlled to avoid health and environmental safety issues. Among solid state detectors, we recently demonstrated that Radiation sensitive OXide Field Effect Transistors (ROXFETs) are excellent candidates for personal dosimetry thanks to their fast response and high sensitivity to x rays. These
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Influence of thickness scaling on the electronic structure and optical properties of oxygen deficient BaBiO3-δ thin films grown on SrTiO3-buffered Si(001) substrate APL Mater. (IF 6.1) Pub Date : 2024-03-05 I. Ahmed, M. Korytov, S. Sergeant, T. Nuytten, T. Conard, S. De Gendt, C. Merckling
BaBiO3 has attracted a lot of research attention since it was discovered as the parent compound for the high-Tc superconducting BaPbxBi1–xO3 and Ba1–xKxBiO3. In its pure state, BaBiO3 is an insulator due to the presence of a breathing distortion of the BiO6 octahedra. The distortion is attributed to the valency of Bi in the compound being charge-ordered in the form of Bi3+ and Bi5+ along the lattice
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Local defect and mid-gap state analysis of GaN using monochromated EELS combined with nanodiffraction and atomic-resolution imaging APL Mater. (IF 6.1) Pub Date : 2024-03-01 Shunsuke Yamashita, Sei Fukushima, Jun Kikkawa, Ryoji Arai, Yuya Kanitani, Koji Kimoto, Yoshihiro Kudo
Defects in semiconductor materials significantly impact their inherent properties, making the evaluation of local defects and their energy levels crucial for controlling device performance. With advancements in monochromators, electron energy loss spectroscopy (EELS) combined with scanning transmission electron microscopy (STEM) has emerged as a promising approach for assessing crystal and band structures
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Air stability and composition evolution in van der Waals Fe3GeTe2 APL Mater. (IF 6.1) Pub Date : 2024-03-01 Weiran Xie, Jie Zhang, Yue Bai, Yingjie Liu, Hangtian Wang, Peiyuan Yu, Jing Li, Hao Chang, Zili Wang, Fan Gao, Guodong Wei, Weisheng Zhao, Tianxiao Nie
Layered two-dimensional ferromagnetic materials have emerged as a promising platform for spintronic applications, owing to their extraordinary physical properties. Remarkably, the representative two-dimensional ferromagnet Fe3GeTe2 has been extensively investigated due to its high Curie temperature and strong perpendicular magnetic anisotropy, which are beneficial for high-density storage at room temperature
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Y3Fe5O12 film with multi-domain epitaxy on single-crystalline LiNbO3 substrate APL Mater. (IF 6.1) Pub Date : 2024-02-29 Kazuto Yamanoi, Kenta Hase, Sachio Komori, Tomoyasu Taniyama, Yukio Nozaki
Y3Fe5O12 is one of the magnetic insulators that can realize high-speed and low-power-consuming spintronics devices. However, it is hard to prepare a high-quality Y3Fe5O12 film via a conventional sputtering process owing to its low crystalline texture, which leads to a crucial increase in the Gilbert damping constant. Moreover, a single crystalline Gd3Ga5O12 substrate, whose lattice constant is well
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On Mars as it is on Earth: Bioinspired technologies for sustainability on Earth are paving the way for a new era of space exploration APL Mater. (IF 6.1) Pub Date : 2024-02-29 Javier G. Fernandez, Shiwei Ng
This Perspective explores the synergy between bioinspired technologies for sustainability on Earth and their application in space exploration. We focus on the parallels between the paradigm shift toward sustainable development on our planet and establishing permanent human settlements on Mars and the Moon. Informed by Earth’s ecological and technological progress, which emphasizes the critical need
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Machine learning investigation of high-k metal gate processes for dynamic random access memory peripheral transistor APL Mater. (IF 6.1) Pub Date : 2024-02-29 Namyong Kwon, JoonHo Bang, Won Ju Sung, Jung Hoon Han, Dongin Lee, Ilwoo Jung, Se Guen Park, Hyodong Ban, Sangjoon Hwang, Won Yong Shin, Jinhye Bae, Dongwoo Lee
Dynamic random access memory (DRAM) plays a crucial role as a memory device in modern computing, and the high-k/metal gate (HKMG) process is essential for enhancing DRAM’s power efficiency and performance. However, integration of the HKMG process into the existing DRAM technology presents complex and time-consuming challenges. This research uses machine learning analysis to investigate the relationships
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Microwave characterization of tantalum superconducting resonators on silicon substrate with niobium buffer layer APL Mater. (IF 6.1) Pub Date : 2024-02-29 Yoshiro Urade, Kay Yakushiji, Manabu Tsujimoto, Takahiro Yamada, Kazumasa Makise, Wataru Mizubayashi, Kunihiro Inomata
Tantalum thin films sputtered on unheated silicon substrates are characterized with microwaves at around 10 GHz in a 10 mK environment. We show that the phase of tantalum with a body-centered cubic lattice (α-Ta) can be grown selectively by depositing a niobium buffer layer prior to a tantalum film. The physical properties of the films, such as superconducting transition temperature and crystallinity
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Homogenization of Inconel 625 based periodic auxetic lattice structures with varying strut thickness APL Mater. (IF 6.1) Pub Date : 2024-02-27 Akshansh Mishra, Vijaykumar S. Jatti, Eyob Messele Sefene, Emad Makki
The purpose of this research is to analyze the mechanical behavior of auxetic re-entrant-based metamaterials with properties similar to Inconel 625 using homogenization techniques. Through a thorough analysis, this study investigates the displacement patterns exhibited in various materials throughout a range of thicknesses. The examination also includes analyzing how the Young’s modulus changes with
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Robust catalyst 3D microarchitectures by digital light printing with ceramic particle–polymer composites APL Mater. (IF 6.1) Pub Date : 2024-02-27 Do Hyeog Kim, Sang-Hoon Nam, Gina Han, Seo Rim Park, Gwang Ho Jeong, Seok Kim, Young Tae Cho, Nicholas Xuanlai Fang
This study entailed the development of an advanced photocatalyst model characterized by high efficiency and ease in dispersion and retrieval processes. This model incorporates a multiscale-hierarchical open-cell structure integrated with nanostructured materials, effectively targeting the removal of organic compounds from wastewater. The fabrication of the specimens was achieved through a combined
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Sputtered NbN films for ultrahigh performance superconducting nanowire single-photon detectors APL Mater. (IF 6.1) Pub Date : 2024-02-27 Ilya A. Stepanov, Aleksandr S. Baburin, Danil V. Kushnev, Evgeniy V. Sergeev, Oksana I. Shmonina, Aleksey R. Matanin, Vladimir V. Echeistov, Ilya A. Ryzhikov, Yuri V. Panfilov, Ilya A. Rodionov
At the present time, ultrahigh performance superconducting nanowire single-photon detectors are the key elements in a variety of devices from biological research to quantum communications and computing. Accurate tuning of superconducting material properties is a powerful resource for fabricating single-photon detectors with desired properties. Here, we report on the major theoretical relations between
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Optomechanical methodology for characterizing the thermal properties of 2D materials APL Mater. (IF 6.1) Pub Date : 2024-02-26 Hanqing Liu, Hatem Brahmi, Carla Boix-Constant, Herre S. J. van der Zant, Peter G. Steeneken, Gerard J. Verbiest
Heat transport in two dimensions is fundamentally different from that in three dimensions. As a consequence, the thermal properties of 2D materials are of great interest, from both scientific and application points of view. However, few techniques are available for the accurate determination of these properties in ultrathin suspended membranes. Here, we present an optomechanical methodology for extracting
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Effect of methanol and photoinduced surface oxygen vacancies on the charge carrier dynamics in TiO2 APL Mater. (IF 6.1) Pub Date : 2024-02-23 Orcun Dincer, Bugrahan Guner, Omur E. Dagdeviren
The migration of holes in metal-oxide semiconductors such as TiO2 plays a vital role in (photo)catalytic applications. The dynamics of charge carriers under operation conditions can be influenced by both methanol addition and photoinduced surface oxygen vacancies (PI-SOVs). Nevertheless, the existing knowledge of the effect of methanol as a function of PI-SOVs solely concentrates on the chemical reduction
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Shubnikov–de Haas oscillations of biaxial-strain-tuned superconductors in pulsed magnetic field up to 60 T APL Mater. (IF 6.1) Pub Date : 2024-02-21 King Yau Yip, Lingfei Wang, Tsz Fung Poon, Kai Ham Yu, Siu Tung Lam, Kwing To Lai, John Singleton, Fedor F. Balakirev, Swee K. Goh
Two-dimensional (2D) materials have gained increasing prominence not only in fundamental research but also in daily applications. However, to fully harness their potential, it is crucial to optimize their properties with an external parameter and track the electronic structure simultaneously. Magnetotransport over a wide magnetic field range is a powerful method to probe the electronic structure and
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Application of nanogenerators in acoustics based on artificial intelligence and machine learning APL Mater. (IF 6.1) Pub Date : 2024-02-21 Xiaofei Yu, Tengtian Ai, Kai Wang
As artificial intelligence (AI) advances, it is critical to give conventional electronics the capacity to “think,” “analyze,” and “advise.” The need for intelligent, self-powered devices has increased due to recent significant developments in the computer field, namely, in the fields of AI and machine learning (ML). The use of nanogenerators in the area of acoustics is examined in this Review, with
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Optical and microstructural characterization of Er3+ doped epitaxial cerium oxide on silicon APL Mater. (IF 6.1) Pub Date : 2024-02-20 Gregory D. Grant, Jiefei Zhang, Ignas Masiulionis, Swarnabha Chattaraj, Kathryn E. Sautter, Sean E. Sullivan, Rishi Chebrolu, Yuzi Liu, Jessica B. Martins, Jens Niklas, Alan M. Dibos, Sumit Kewalramani, John W. Freeland, Jianguo Wen, Oleg G. Poluektov, F. Joseph Heremans, David D. Awschalom, Supratik Guha
Rare-earth ion dopants in solid-state hosts are ideal candidates for quantum communication technologies, such as quantum memories, due to the intrinsic spin–photon interface of the rare-earth ion combined with the integration methods available in the solid state. Erbium-doped cerium oxide (Er:CeO2) is a particularly promising host material platform for such a quantum memory, as it combines the telecom-wavelength
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High thermoelectric performance in polycrystalline Yb3Ge5 thin films APL Mater. (IF 6.1) Pub Date : 2024-02-20 T. Ishiyama, T. Ozawa, N. Saitoh, N. Yoshizawa, T. Suemasu, K. Toko
The development of eco-friendly thin-film thermoelectric generators for microenergy harvesting applications is highly desired. Ge-based materials have recently attracted significant research interest because of their superior performance at room temperature as human-compatible thermoelectric constituents. We examined the synthesis of Yb3Ge5 thin films and assessed their thermoelectric properties, considering
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Enhanced magnetic field concentration using windmill-like ferromagnets APL Mater. (IF 6.1) Pub Date : 2024-02-20 Natanael Bort-Soldevila, Jaume Cunill-Subiranas, Aleix Barrera, Nuria Del-Valle, Alejandro V. Silhanek, Vojtěch Uhlíř, Simon Bending, Anna Palau, Carles Navau
Magnetic sensors are used in many technologies and industries, such as medicine, telecommunications, robotics, the Internet of Things, etc. The sensitivity of these magnetic sensors is a key aspect, as it determines their precision. In this article, we investigate how a thin windmill-like ferromagnetic system can hugely concentrate a magnetic field at its core. A magnetic sensor combined with such
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Structural and optical characterization of dilute Bi-doped GaN nanostructures grown by molecular beam epitaxy APL Mater. (IF 6.1) Pub Date : 2024-02-20 Ishtiaque Ahmed Navid, Yujie Liu, Yuyang Pan, Kai Sun, Emmanouil Kioupakis, Zetian Mi
We have carried out detailed studies on the epitaxy and characterization of dilute Bi-doped GaN nanostructures. A comprehensive investigation of Bi-doped GaN nanowires and quasi-film epitaxial growth conditions has been performed. Scanning electron microscopy studies show that lowering the GaBiN growth temperature causes gradual changes in top c-plane nanowire morphology due to the incremental incorporation
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Interface-induced transverse resistivity anomaly in AgNbO3/SrRuO3 heterostructures APL Mater. (IF 6.1) Pub Date : 2024-02-20 Ruxin Liu, Ruijie Xu, Yequan Chen, Liqi Zhou, Wenzhuo Zhuang, Xu Zhang, Chong Zhang, Zhongqiang Chen, Liming Chen, Xuefeng Wang
The transverse resistivity anomaly with a hump feature, associated with topological magnetic textures, is of paramount importance for the applications of next-generation chiral spintronic devices. However, the origin of the hump feature still remains debated due to the complicated mechanism, not merely assigned to the intrinsic topological Hall effect (THE). In this work, we observe the apparent transverse
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The 1/4 occupied O atoms induced ultra-flatband and the one-dimensional channels in the Pb10−xCux(PO4)6O4 (x = 0, 0.5) crystal APL Mater. (IF 6.1) Pub Date : 2024-02-20 Kun Tao, Rongrong Chen, Lei Yang, Jin Gao, Desheng Xue, Chenglong Jia
The search for room-temperature superconductors has been a long-standing goal in condensed matter physics. In this study, we investigate the electronic and geometric properties of lead apatite with and without Cu doping within the framework of the density functional theory. Based on our calculations, we found that without Cu doping, the lead apatite PPOO shows an insulator character with flatbands
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Experimental investigation of Rayleigh wave propagation in a locally resonant metamaterial layer resting on an elastic half-space APL Mater. (IF 6.1) Pub Date : 2024-02-16 Farhad Zeighami, Antonio Palermo, Denis Bogomolov, Alessandro Marzani
In this experimental investigation, we explore the propagation characteristics of surface Rayleigh waves in a Locally Resonant Metamaterial (LRM) layer positioned on an elastic half-space. The study focuses on characterizing the dispersion and attenuation properties of these waves and validating analytical and numerical models of the LRM. For practical purposes, we utilize a thin-plate sample and construct
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Fabrication and photonic applications of Si-integrated LiNbO3 and BaTiO3 ferroelectric thin films APL Mater. (IF 6.1) Pub Date : 2024-02-16 Yiyang Wen, Haisheng Chen, Zhenping Wu, Wei Li, Yang Zhang
Silicon, renowned for its applications in electronic circuits, also offers significant advantages in the realm of integrated optics. While silicon does have inherent limitations in fabricating active devices, these challenges can be overcome through heterogeneous integration with other materials. Ferroelectric materials like lithium niobate (LN) and barium titanate (BTO) exhibit exceptional electrical
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Imaging the magnetic nanowire cross section and magnetic ordering within a suspended 3D artificial spin-ice APL Mater. (IF 6.1) Pub Date : 2024-02-16 Edward Harding, Tohru Araki, Joseph Askey, Matthew Hunt, Arjen Van Den Berg, David Raftrey, Lucia Aballe, Burkhard Kaulich, Emyr MacDonald, Peter Fischer, Sam Ladak
Artificial spin-ice systems are patterned arrays of magnetic nanoislands arranged into frustrated geometries and provide insight into the physics of ordering and emergence. The majority of these systems have been realized in two-dimensions, mainly due to the ease of fabrication, but with recent developments in advanced nanolithography, three-dimensional artificial spin ice (ASI) structures have become
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Control of growth kinetics during remote epitaxy of complex oxides on graphene by pulsed laser deposition APL Mater. (IF 6.1) Pub Date : 2024-02-16 M. A. Wohlgemuth, U. Trstenjak, A. Sarantopoulos, F. Gunkel, R. Dittmann
Remote epitaxy through 2D materials opens new opportunities for research and application, overcoming some limitations of classical epitaxy and allowing the creation of freestanding layers. However, using graphene as a 2D interlayer for remote epitaxy of metal oxides is challenging, particularly when carried out by pulsed laser deposition (PLD). The graphene layer can be easily oxidized under the typically
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Nano-positive up negative down in binary oxide ferroelectrics APL Mater. (IF 6.1) Pub Date : 2024-02-16 Andres Gomez, Umberto Celano
Ferroelectric HfO2 and ZrO2-based materials are promising candidates for next-generation ferroelectric devices, but their characterization is challenging due to complex factors such as crystal phases, degradation mechanisms, and local inhomogeneities. In this work, we propose a novel nanosized positive-up-negative-down (PUND) method to assess the ferroelectric response of doped-HfO2. This method is
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Orbital ordering and ultrafast carrier dynamics anisotropies in orientation-engineered orthorhombic YMnO3 films APL Mater. (IF 6.1) Pub Date : 2024-02-16 My Ngoc Duong, Yu-Xun Chen, Wen-Yen Tzeng, Tahta Amrillah, Song Yang, Cheng-En Liu, Dimitre Z. Dimitrov, Shu-Chih Haw, Chia-Hung Hsu, Jin-Ming Chen, Jiunn-Yuan Lin, Kaung-Hsiung Wu, Chih-Wei Luo, Chien-Te Chen, Chang-Yang Kuo, Jenh-Yih Juang
The rich physical properties unveiled in a plethora of transition and rare-earth metal oxides have been attributed to the intricate interplays between the orbital, charge, and spin degrees of freedom. Among them, rare-earth manganites (RMnO3) have been attracting tremendous attention owing to the ionic size-induced lattice distortion dictated by the Goldschmidt tolerance factor and the substantial
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Electron effective mass in GaN revisited: New insights from terahertz and mid-infrared optical Hall effect APL Mater. (IF 6.1) Pub Date : 2024-02-16 Nerijus Armakavicius, Sean Knight, Philipp Kühne, Vallery Stanishev, Dat Q. Tran, Steffen Richter, Alexis Papamichail, Megan Stokey, Preston Sorensen, Ufuk Kilic, Mathias Schubert, Plamen P. Paskov, Vanya Darakchieva
Electron effective mass is a fundamental material parameter defining the free charge carrier transport properties, but it is very challenging to be experimentally determined at high temperatures relevant to device operation. In this work, we obtain the electron effective mass parameters in a Si-doped GaN bulk substrate and epitaxial layers from terahertz (THz) and mid-infrared (MIR) optical Hall effect
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Quartic-root higher-order topological insulators on decorated three-dimensional sonic crystals APL Mater. (IF 6.1) Pub Date : 2024-02-11 Zhi-Guo Geng, Ya-Xi Shen, Zhan Xiong, Liwei Duan, Zhaojiang Chen, Xue-Feng Zhu
The square-root operation provides a new scheme to create topological phases with unconventional spectrum properties. With the square-root operation, the square-root topological insulators can support paired topological boundary states in two bulk gaps, and the mechanism of square-root has been generalized to 2n-root topological insulators. In this study, we describe the acoustic realization of third-order
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Broad luminescence from Zn acceptors in Zn doped β-Ga2O3 APL Mater. (IF 6.1) Pub Date : 2024-02-11 Ylva K. Hommedal, Ymir K. Frodason, Augustinas Galeckas, Lasse Vines, Klaus Magnus H. Johansen
Zn-related defects in β-Ga2O3 were studied using photoluminescence (PL) spectroscopy combined with hybrid functional calculations and secondary ion mass spectrometry. We have in-diffused Zn by heat treatments of β-Ga2O3 in Zn vapor to promote the formation of the ZnGaZni complex as the dominating Zn configuration. Subsequently, we did heat treatment in oxygen ambient to study the dissociation of the
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Strategies for hardening purity metallic materials by high pressure and high temperature quenching method APL Mater. (IF 6.1) Pub Date : 2024-02-11 Xingbin Zhao, Hao Jiang, Kuo Bao, Yanping Huang, Shuailing Ma, Pinwen Zhu, Qiang Tao, Tian Cui
Purity metallic materials are increasingly demanded in modern manufacturing industries, but their applications are limited owing to their poor wear resistance and mechanical properties. Therefore, exploring an efficient hardening method to significantly enhance the hardness of pure metals is emergent in materials science. In this work, a series of high pressure and high temperature (HPHT) quenching
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Effect of boron concentration on local structure and spontaneous polarization in AlBN thin films APL Mater. (IF 6.1) Pub Date : 2024-02-11 S. Calderon V, John Hayden, M. Delower, Jon-Paul Maria, Elizabeth C. Dickey
The discovery of ferroelectricity in polar wurtzite-based ternary materials, such as Al1−xBxN, has attracted attention due to their compatibility with complementary metal–oxide–semiconductor processes and potential use in integrated non-volatile memory devices. However, the origin of ferroelectricity and the fundamental control of the polarization switching in these materials are still under intensive
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Towards ultrathin metal-organic frameworks membranes for high-performance separation APL Mater. (IF 6.1) Pub Date : 2024-02-11 Qi Liu, Heng-Yu Chi, Shuqing Song, Ranadip Goswami, Kumar Varoon Agrawal
Research on metal-organic frameworks (MOFs) based membranes has gained a lot of attention in the last decade thanks to the unique and highly versatile chemistry of MOFs, which allows one to synthesize a variety of structural dimensions, topologies, pore sizes, pore shapes, functional groups, and chemical environments. For membrane application, the field is rapidly progressing, with the focus shifting
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Benchmarking inverse optimization algorithms for materials design APL Mater. (IF 6.1) Pub Date : 2024-02-11 Hanfeng Zhai, Hongxia Hao, Jingjie Yeo
Machine learning-based inverse materials discovery has attracted enormous attention recently due to its flexibility in dealing with black box models. Yet, many metaheuristic algorithms are not as widely applied to materials discovery applications as machine learning methods. There are ongoing challenges in applying different optimization algorithms to discover materials with single- or multi-elemental
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Epitaxial growth and characterization of Bi1−xSbx thin films on (0001) sapphire substrates APL Mater. (IF 6.1) Pub Date : 2024-02-11 Yu-Sheng Huang, Saurav Islam, Yongxi Ou, Supriya Ghosh, Anthony Richardella, K. Andre Mkhoyan, Nitin Samarth
We report the molecular beam epitaxy of Bi1−xSbx thin films (0 ≤ x ≤ 1) on sapphire (0001) substrates using a thin (Bi,Sb)2Te3 buffer layer. The characterization of the films using reflection high energy diffraction, x-ray diffraction, atomic force microscopy, and scanning transmission electron microscopy reveals the epitaxial growth of films of reasonable structural quality. This is further confirmed
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Stacked space-folded acoustic metasurfaces for the flexible control of sound absorption APL Mater. (IF 6.1) Pub Date : 2024-02-11 Xin Wang, Jiahao Wang, Zedong Ma, Ilya Deriy, Mingzhao Song, Andrey Bogdanov, Yongyao Chen
Sound absorbing materials capable of working in harsh environments (e.g., fire resistance, moisture resistance, and pressure resistance) while having excellent low-frequency sound absorption properties are highly desirable for many practical applications. Recently, a new class of acoustic absorbers based on space coiling and folding metamaterials (SCFMs) has emerged. The SCFMs could be comprised of
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Temperature and bias voltage dependences of magnetic tunnel junction with FeAlSi electrode APL Mater. (IF 6.1) Pub Date : 2024-02-01 Shoma Akamatsu, Byung Hun Lee, Yasen Hou, Masakiyo Tsunoda, Mikihiko Oogane, Geoffrey S. D. Beach, Jagadeesh S. Moodera
We fabricated magnetic tunnel junctions (MTJs) with FeAlSi free layers and investigated the tunnel magnetoresistance (TMR) properties. We found that the temperature and bias voltage dependences of the TMR effect in FeAlSi-MTJs were almost the same as MTJs with Fe free layers despite the low Curie temperature of FeAlSi. In the inelastic electron tunneling spectroscopy measured at low temperatures, the
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Controllable arrangement of magnetic skyrmions by strain regulation APL Mater. (IF 6.1) Pub Date : 2024-02-01 Yunhong Zhao, Lan Shang, Shengbin Shi, Jiajun Sun, Jie Wang
The efficient manipulation of magnetic skyrmions is crucial for the development of future spintronic devices. Here, we demonstrate the controllable arrangement of magnetic skyrmions through strain regulation in the bilayer film system composed of piezoelectric and ferromagnetic layers. The motion characteristics and energy distribution of skyrmions in the ferromagnetic layer under an in-plane periodic
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Coherent optical response driven by non-equilibrium electron–phonon dynamics in a layered transition-metal dichalcogenide APL Mater. (IF 6.1) Pub Date : 2024-02-01 Takumi Fukuda, Kotaro Makino, Yuta Saito, Paul Fons, Atsushi Ando, Takuya Mori, Ryo Ishikawa, Keiji Ueno, Jessica Afalla, Muneaki Hase
Layered transition-metal dichalcogenides (TMDs) are model systems to explore ultrafast many-body interactions and various nonlinear optical phenomena. For the application of TMD-based optoelectronic devices capable of ultrafast response, it is essential to understand how characteristic electron–hole and electron–phonon couplings modify ultrafast electronic and optical properties under photoexcitation
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The characteristics of Cu-doped lead apatite (LK-99) synthesized with the removal of Cu2S using ammonia solution: A diamagnetic semiconductor APL Mater. (IF 6.1) Pub Date : 2024-02-01 Zhujialei Lei, Chin-Wei Lin, I-Nan Chen, Chun-Tse Chou, Yen-Lin Lin, Jau-Han Chen, Huang-Huei Sung, Li-Min Wang
This study evaluated the superconducting properties of Cu-doped lead apatite “LK-99” and synthesized LK-99 samples using the process proposed by a team from Korea, who first described the process. Additionally, whether the results of this Korean team were related to Cu2S was also examined using an ammonia solution (NH3·H2O) to remove Cu2S. Through x-ray diffraction (XRD) and energy dispersive x-ray