Ren Wang, Pan-Yi Bao, Zhi-Qiang Hu, Shuai Shi, Bing-Zhong Wang, Nikolay I. Zheludev, Yijie Shen
Toroidal electromagnetic pulses have been recently reported as nontransverse, space-time nonseparable topological excitations of free space. However, their propagation dynamics and topological configurations have not been comprehensively experimentally characterized. In addition, the existing generators were limited in optical and terahertz domains; however, the feasibility and significance of generating such pulses at microwave frequencies have been overlooked. Here, we report that microwave toroidal pulses can be launched by a transient finite-aperture broadband horn antenna emitter, as an electromagnetic counterpart of “air vortex cannon.” Applying this effective generator, we experimentally map the toroidal pulses' topological skyrmionic textures in free space and demonstrate their resilient propagation dynamics, i.e., how that, during propagation, the pulses evolve toward stronger space-time nonseparability and closer proximity to the canonical Hellwarth–Nouchi toroidal pulses. Our work offers a practical opportunity for using topologically robust toroidal pulses as information carriers in high-capacity telecom, cell phone technology, remote sensing, and global positioning, especially where microwave frequencies are predominant.
{"title":"Observation of resilient propagation and free-space skyrmions in toroidal electromagnetic pulses","authors":"Ren Wang, Pan-Yi Bao, Zhi-Qiang Hu, Shuai Shi, Bing-Zhong Wang, Nikolay I. Zheludev, Yijie Shen","doi":"10.1063/5.0218207","DOIUrl":"https://doi.org/10.1063/5.0218207","url":null,"abstract":"Toroidal electromagnetic pulses have been recently reported as nontransverse, space-time nonseparable topological excitations of free space. However, their propagation dynamics and topological configurations have not been comprehensively experimentally characterized. In addition, the existing generators were limited in optical and terahertz domains; however, the feasibility and significance of generating such pulses at microwave frequencies have been overlooked. Here, we report that microwave toroidal pulses can be launched by a transient finite-aperture broadband horn antenna emitter, as an electromagnetic counterpart of “air vortex cannon.” Applying this effective generator, we experimentally map the toroidal pulses' topological skyrmionic textures in free space and demonstrate their resilient propagation dynamics, i.e., how that, during propagation, the pulses evolve toward stronger space-time nonseparability and closer proximity to the canonical Hellwarth–Nouchi toroidal pulses. Our work offers a practical opportunity for using topologically robust toroidal pulses as information carriers in high-capacity telecom, cell phone technology, remote sensing, and global positioning, especially where microwave frequencies are predominant.","PeriodicalId":8200,"journal":{"name":"Applied physics reviews","volume":"215 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2024-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141880368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
He Gao, Weiwei Zhu, Haoran Xue, Guancong Ma, Zhongqing Su
Non-Hermitian skin effect (NHSE) is an intrinsic non-Hermitian phenomenon where an extensive number of eigenmodes, called skin modes, are localized at the boundary of a system. Recent theories have suggested that the NHSE can be well-tuned by external fields, opening a route to manipulating wave localization. Here, we experimentally demonstrate the diverse interactions between NHSE and synthetic magnetic fields (SMFs) in coupled acoustic ring resonator lattices. We observe that the NHSE and SMFs can, via different physical mechanisms, compete or synergize, resulting in either the suppression or the creation of NHSE. With the aid of the complex frequency excitation technique, we experimentally observe that SMFs can suppress the NHSE by introducing Landau quantization, causing localization to move toward the bulk. In contrast, we show that the presence of SMF generates topological edge modes in the lattice, which then become corner skin modes by the second-order NHSE. Our results evidence the rich physics and diverse consequences that arise from the interplay of magnetic fields and NHSE, paving the way for actively controlling wave localization.
{"title":"Controlling acoustic non-Hermitian skin effect via synthetic magnetic fields","authors":"He Gao, Weiwei Zhu, Haoran Xue, Guancong Ma, Zhongqing Su","doi":"10.1063/5.0213867","DOIUrl":"https://doi.org/10.1063/5.0213867","url":null,"abstract":"Non-Hermitian skin effect (NHSE) is an intrinsic non-Hermitian phenomenon where an extensive number of eigenmodes, called skin modes, are localized at the boundary of a system. Recent theories have suggested that the NHSE can be well-tuned by external fields, opening a route to manipulating wave localization. Here, we experimentally demonstrate the diverse interactions between NHSE and synthetic magnetic fields (SMFs) in coupled acoustic ring resonator lattices. We observe that the NHSE and SMFs can, via different physical mechanisms, compete or synergize, resulting in either the suppression or the creation of NHSE. With the aid of the complex frequency excitation technique, we experimentally observe that SMFs can suppress the NHSE by introducing Landau quantization, causing localization to move toward the bulk. In contrast, we show that the presence of SMF generates topological edge modes in the lattice, which then become corner skin modes by the second-order NHSE. Our results evidence the rich physics and diverse consequences that arise from the interplay of magnetic fields and NHSE, paving the way for actively controlling wave localization.","PeriodicalId":8200,"journal":{"name":"Applied physics reviews","volume":"74 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2024-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141862291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cavity optomechanical (COM) sensors, featuring efficient light–motion couplings, have been widely used for ultrasensitive measurements of various physical quantities ranging from displacements to accelerations or weak forces. Previous works, however, have mainly focused on reciprocal COM systems. Here, we propose how to further improve the performance of quantum COM sensors by breaking reciprocal symmetry in purely quantum regime. Specifically, we consider a spinning COM resonator and show that by selectively driving it in opposite directions, highly nonreciprocal optical squeezing can emerge, which in turn provides an efficient way to surpass the standard quantum limit which is otherwise unattainable for the corresponding reciprocal devices. Our work confirms that breaking reciprocal symmetry, already achieved in diverse systems well beyond spinning systems, can serve as a new strategy to further enhance the abilities of advanced quantum sensors, for applications ranging from testing fundamental physical laws to practical quantum metrology.
空腔光机械（COM）传感器具有高效的光-动耦合特性，已被广泛用于超灵敏测量从位移到加速度或微弱力等各种物理量。然而，以前的工作主要集中在往复式 COM 系统上。在此，我们提出如何通过打破纯量子体系中的互对称性来进一步提高量子 COM 传感器的性能。具体来说，我们考虑了一个旋转 COM 谐振器，并证明了通过选择性地向相反方向驱动它，可以出现高度非互易的光学挤压，这反过来又提供了一种超越标准量子极限的有效方法，否则相应的互易器件是无法实现的。我们的工作证实，打破互易对称性已经在各种系统中实现，远远超出了旋转系统的范围，它可以作为一种新策略，进一步增强先进量子传感器的能力，应用范围从基本物理定律测试到实用量子计量学。
{"title":"Quantum advantage of one-way squeezing in weak-force sensing","authors":"Jie Wang, Qian Zhang, Ya-Feng Jiao, Sheng-Dian Zhang, Tian-Xiang Lu, Zhipeng Li, Cheng-Wei Qiu, Hui Jing","doi":"10.1063/5.0208107","DOIUrl":"https://doi.org/10.1063/5.0208107","url":null,"abstract":"Cavity optomechanical (COM) sensors, featuring efficient light–motion couplings, have been widely used for ultrasensitive measurements of various physical quantities ranging from displacements to accelerations or weak forces. Previous works, however, have mainly focused on reciprocal COM systems. Here, we propose how to further improve the performance of quantum COM sensors by breaking reciprocal symmetry in purely quantum regime. Specifically, we consider a spinning COM resonator and show that by selectively driving it in opposite directions, highly nonreciprocal optical squeezing can emerge, which in turn provides an efficient way to surpass the standard quantum limit which is otherwise unattainable for the corresponding reciprocal devices. Our work confirms that breaking reciprocal symmetry, already achieved in diverse systems well beyond spinning systems, can serve as a new strategy to further enhance the abilities of advanced quantum sensors, for applications ranging from testing fundamental physical laws to practical quantum metrology.","PeriodicalId":8200,"journal":{"name":"Applied physics reviews","volume":"18 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141857711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ordered porous carbon materials with regularly arranged pores and adjustable pore sizes have attracted significant attention due to their versatile applications across various fields. In this context, uniform carbon coating of anodic aluminum oxide (AAO) membranes is an effective approach to fabricating an ordered array of cylindrical carbonaceous nanopores with adjustable pore diameter and length. The resulting carbon-coated AAO (C/AAO) composite exhibits a meticulously ordered array of meso/macropores, devoid of inter-particle pores and resistance, setting it apart from conventional ordered porous carbons with powder forms. The pore dimensions of C/AAO can be precisely controlled over a wide range, and the carbon chemistry can be customized through heteroatom doping and chemical modifications, all without altering the pore structure. These inherent advantages position C/AAO as a highly promising material with broad application prospects. This review article provides a comprehensive overview of the synthesis and characterization of C/AAO and related materials, along with their diverse utilization in the fields of optics, field emission, gas sensing, energy storage, electrocatalyst support, and bionics. Furthermore, an outlook on the C/AAO materials is given at the end, highlighting their potential and associated challenges.
{"title":"Carbon-coated anodic aluminum oxide: Synthesis, characterization, and applications","authors":"Hongyu Liu, Zheng-Ze Pan, Tetsuji Itoh, Takashi Kyotani, Hirotomo Nishihara","doi":"10.1063/5.0210821","DOIUrl":"https://doi.org/10.1063/5.0210821","url":null,"abstract":"Ordered porous carbon materials with regularly arranged pores and adjustable pore sizes have attracted significant attention due to their versatile applications across various fields. In this context, uniform carbon coating of anodic aluminum oxide (AAO) membranes is an effective approach to fabricating an ordered array of cylindrical carbonaceous nanopores with adjustable pore diameter and length. The resulting carbon-coated AAO (C/AAO) composite exhibits a meticulously ordered array of meso/macropores, devoid of inter-particle pores and resistance, setting it apart from conventional ordered porous carbons with powder forms. The pore dimensions of C/AAO can be precisely controlled over a wide range, and the carbon chemistry can be customized through heteroatom doping and chemical modifications, all without altering the pore structure. These inherent advantages position C/AAO as a highly promising material with broad application prospects. This review article provides a comprehensive overview of the synthesis and characterization of C/AAO and related materials, along with their diverse utilization in the fields of optics, field emission, gas sensing, energy storage, electrocatalyst support, and bionics. Furthermore, an outlook on the C/AAO materials is given at the end, highlighting their potential and associated challenges.","PeriodicalId":8200,"journal":{"name":"Applied physics reviews","volume":"13 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141768599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Carlos Ezio Garciamendez-Mijares, Francisco Javier Aguilar, Pavel Hernandez, Xiao Kuang, Mauricio Gonzalez, Vanessa Ortiz, Ricardo A. Riesgo, David S. Rendon Ruiz, Victoria Abril Manjarrez Rivera, Juan Carlos Rodriguez, Francisco Lugo Mestre, Penelope Ceron Castillo, Abraham Perez, Lourdes Monserrat Cruz, Khoon S. Lim, Yu Shrike Zhang
With the rapid development and popularization of additive manufacturing, different technologies, including, but not limited to, extrusion-, droplet-, and vat-photopolymerization-based fabrication techniques, have emerged that have allowed tremendous progress in three-dimensional (3D) printing in the past decades. Bioprinting, typically using living cells and/or biomaterials conformed by different printing modalities, has produced functional tissues. As a subclass of vat-photopolymerization bioprinting, digital light processing (DLP) uses digitally controlled photomasks to selectively solidify liquid photocurable bioinks to construct complex physical objects in a layer-by-layer manner. DLP bioprinting presents unique advantages, including short printing times, relatively low manufacturing costs, and decently high resolutions, allowing users to achieve significant progress in the bioprinting of tissue-like complex structures. Nevertheless, the need to accommodate different materials while bioprinting and improve the printing performance has driven the rapid progress in DLP bioprinters, which requires multiple pieces of knowledge ranging from optics, electronics, software, and materials beyond the biological aspects. This raises the need for a comprehensive review to recapitulate the most important considerations in the design and assembly of DLP bioprinters. This review begins with analyzing unique considerations and specific examples in the hardware, including the resin vat, optical system, and electronics. In the software, the workflow is analyzed, including the parameters to be considered for the control of the bioprinter and the voxelizing/slicing algorithm. In addition, we briefly discuss the material requirements for DLP bioprinting. Then, we provide a section with best practices and maintenance of a do-it-yourself DLP bioprinter. Finally, we highlight the future outlooks of the DLP technology and their critical role in directing the future of bioprinting. The state-of-the-art progress in DLP bioprinter in this review will provide a set of knowledge for innovative DLP bioprinter designs.
{"title":"Design considerations for digital light processing bioprinters","authors":"Carlos Ezio Garciamendez-Mijares, Francisco Javier Aguilar, Pavel Hernandez, Xiao Kuang, Mauricio Gonzalez, Vanessa Ortiz, Ricardo A. Riesgo, David S. Rendon Ruiz, Victoria Abril Manjarrez Rivera, Juan Carlos Rodriguez, Francisco Lugo Mestre, Penelope Ceron Castillo, Abraham Perez, Lourdes Monserrat Cruz, Khoon S. Lim, Yu Shrike Zhang","doi":"10.1063/5.0187558","DOIUrl":"https://doi.org/10.1063/5.0187558","url":null,"abstract":"With the rapid development and popularization of additive manufacturing, different technologies, including, but not limited to, extrusion-, droplet-, and vat-photopolymerization-based fabrication techniques, have emerged that have allowed tremendous progress in three-dimensional (3D) printing in the past decades. Bioprinting, typically using living cells and/or biomaterials conformed by different printing modalities, has produced functional tissues. As a subclass of vat-photopolymerization bioprinting, digital light processing (DLP) uses digitally controlled photomasks to selectively solidify liquid photocurable bioinks to construct complex physical objects in a layer-by-layer manner. DLP bioprinting presents unique advantages, including short printing times, relatively low manufacturing costs, and decently high resolutions, allowing users to achieve significant progress in the bioprinting of tissue-like complex structures. Nevertheless, the need to accommodate different materials while bioprinting and improve the printing performance has driven the rapid progress in DLP bioprinters, which requires multiple pieces of knowledge ranging from optics, electronics, software, and materials beyond the biological aspects. This raises the need for a comprehensive review to recapitulate the most important considerations in the design and assembly of DLP bioprinters. This review begins with analyzing unique considerations and specific examples in the hardware, including the resin vat, optical system, and electronics. In the software, the workflow is analyzed, including the parameters to be considered for the control of the bioprinter and the voxelizing/slicing algorithm. In addition, we briefly discuss the material requirements for DLP bioprinting. Then, we provide a section with best practices and maintenance of a do-it-yourself DLP bioprinter. Finally, we highlight the future outlooks of the DLP technology and their critical role in directing the future of bioprinting. The state-of-the-art progress in DLP bioprinter in this review will provide a set of knowledge for innovative DLP bioprinter designs.","PeriodicalId":8200,"journal":{"name":"Applied physics reviews","volume":"60 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2024-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141768565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Peyala Dharmaiah, Sung-Jin Jung, Jin-Sang Kim, Seong Keun Kim, Seung-Hyub Baek
The successful application of nanotechnologies in enhancing thermoelectric properties of n-type Bi2Te3 alloys remains a formidable challenge, despite significant advancements in their p-type counterparts. The distinctive challenges inherent to n-type materials include the complex relationships between defect structures and electron concentration, and the strong anisotropy of thermoelectric properties. Electrons originate from various defect structures, such as impurity dopants, vacancies, antisite defects, and grain/domain boundaries, which sensitively varies depending on material synthesis processes. Moreover, the pronounced anisotropic nature of thermoelectric properties requires grain alignment along specific crystallographic directions. Therefore, the challenges in achieving high-performance n-type Bi2Te3 alloys lie in the difficulties of independently controlling defect structures (electron concentration), textured microstructures (electron/phonon transport property), and nanofeatures. This review aims to provide a comprehensive understanding of the difficulties and challenges associated with these aspects, and to discuss potential routes for realizing high-performance n-type Bi2Te3 alloys.
尽管在 n 型 Bi2Te3 合金的 p 型材料方面取得了重大进展，但成功应用纳米技术增强其热电特性仍然是一项艰巨的挑战。n 型材料固有的独特挑战包括缺陷结构与电子浓度之间的复杂关系，以及热电特性的强烈各向异性。电子来自各种缺陷结构，如杂质掺杂物、空位、反位元缺陷和晶粒/晶域边界，其敏感性随材料合成工艺的不同而变化。此外，热电特性明显的各向异性要求晶粒沿着特定的晶体学方向排列。因此，实现高性能 n 型 Bi2Te3 合金的挑战在于难以独立控制缺陷结构（电子浓度）、纹理微结构（电子/声子传输特性）和纳米特性。本综述旨在全面了解与这些方面相关的困难和挑战，并探讨实现高性能 n 型 Bi2Te3 合金的潜在途径。
{"title":"Why is it challenging to improve the thermoelectric properties of n-type Bi2Te3 alloys?","authors":"Peyala Dharmaiah, Sung-Jin Jung, Jin-Sang Kim, Seong Keun Kim, Seung-Hyub Baek","doi":"10.1063/5.0205096","DOIUrl":"https://doi.org/10.1063/5.0205096","url":null,"abstract":"The successful application of nanotechnologies in enhancing thermoelectric properties of n-type Bi2Te3 alloys remains a formidable challenge, despite significant advancements in their p-type counterparts. The distinctive challenges inherent to n-type materials include the complex relationships between defect structures and electron concentration, and the strong anisotropy of thermoelectric properties. Electrons originate from various defect structures, such as impurity dopants, vacancies, antisite defects, and grain/domain boundaries, which sensitively varies depending on material synthesis processes. Moreover, the pronounced anisotropic nature of thermoelectric properties requires grain alignment along specific crystallographic directions. Therefore, the challenges in achieving high-performance n-type Bi2Te3 alloys lie in the difficulties of independently controlling defect structures (electron concentration), textured microstructures (electron/phonon transport property), and nanofeatures. This review aims to provide a comprehensive understanding of the difficulties and challenges associated with these aspects, and to discuss potential routes for realizing high-performance n-type Bi2Te3 alloys.","PeriodicalId":8200,"journal":{"name":"Applied physics reviews","volume":"59 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141764229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yanbei Hou, Ming Gao, Xueyu Bai, Lihua Zhao, Hejun Du, Kun Zhou
Freshwater scarcity is a pressing issue worldwide, and solar steam generators (SSGs) have emerged as a promising device for seawater desalination, harnessing renewable solar energy to facilitate sustainable water evaporation. The facile fabrication approach for SSG with complex topologies to achieve high water evaporation efficiency remains a challenge. Herein, a MIL-101 (Fe)-derived C@Fe3O4 ink was employed to multi-jet fusion (MJF) printing of polymeric porous SSGs with specific topologies. The optimized porous structure endows the printed SSGs with capillary force, greatly promoting water transport. The tree-like topology enables high water evaporation rates under various simulated solar radiation conditions. A finite element model was built to fully understand the light-to-thermal energy conversion and water evaporation processes. Moreover, the MJF-printed SSGs exhibit self-cleaning properties and can automatically remove accumulated salt on their surfaces, enabling sustainable desalination. During prolonged testing, the water evaporation rate of the SSGs remained relatively stable and reached as high as 1.55 kg m−2 h−1. Additionally, the desalinated water met the standards for direct drinking water. This study presents a state-of-the-art technology for producing efficient SSGs for desalination and introduces a novel method for MJF printing of functional nanocomposites.
{"title":"3D printing of bio-inspired porous polymeric solar steam generators for efficient and sustainable desalination","authors":"Yanbei Hou, Ming Gao, Xueyu Bai, Lihua Zhao, Hejun Du, Kun Zhou","doi":"10.1063/5.0200505","DOIUrl":"https://doi.org/10.1063/5.0200505","url":null,"abstract":"Freshwater scarcity is a pressing issue worldwide, and solar steam generators (SSGs) have emerged as a promising device for seawater desalination, harnessing renewable solar energy to facilitate sustainable water evaporation. The facile fabrication approach for SSG with complex topologies to achieve high water evaporation efficiency remains a challenge. Herein, a MIL-101 (Fe)-derived C@Fe3O4 ink was employed to multi-jet fusion (MJF) printing of polymeric porous SSGs with specific topologies. The optimized porous structure endows the printed SSGs with capillary force, greatly promoting water transport. The tree-like topology enables high water evaporation rates under various simulated solar radiation conditions. A finite element model was built to fully understand the light-to-thermal energy conversion and water evaporation processes. Moreover, the MJF-printed SSGs exhibit self-cleaning properties and can automatically remove accumulated salt on their surfaces, enabling sustainable desalination. During prolonged testing, the water evaporation rate of the SSGs remained relatively stable and reached as high as 1.55 kg m−2 h−1. Additionally, the desalinated water met the standards for direct drinking water. This study presents a state-of-the-art technology for producing efficient SSGs for desalination and introduces a novel method for MJF printing of functional nanocomposites.","PeriodicalId":8200,"journal":{"name":"Applied physics reviews","volume":"162 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141755374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nonreciprocal magnetotransport is one of the central topics in spintronics because of its importance for electrically probing magnetic information. Among numerous electrical probes used to read magnetic orders, unidirectional magnetoresistance (UMR), characterized by sign changes upon reversal of either current or magnetization, is currently a matter of great interest and has been identified in various spin–orbit-coupled bilayer systems composed of an (anti)ferromagnetic layer and a nonmagnetic layer with strong spin Hall effect. A recent theoretical work predicts that a spin-anomalous-Hall (SAH) UMR in those metallic conducting bilayers can originate from the spin-anomalous-Hall effect of the ferromagnetic layer and the structural inversion asymmetry. However, this type of UMR has not been reported experimentally. Here, we give the experimental evidence of spin-anomalous-Hall UMR in the light-metal/ferromagnetic-metal Cu/Co bilayers, where the emergence of net nonequilibrium spin density is attributed to the interfacial spin leakage asymmetry due to the spin memory loss effect at the Cu/Co interface and multiple spin reflections. We also show a highly tunable UMR in the Cu/Co/CuOx trilayer by varying the Cu thickness, which is due to the competition between the orbital Rashba effect in Co/CuOx and the spin-anomalous-Hall effect in Cu/Co. Our work widens the material choice for UMR device applications and provides an alternative approach to detect in-plane magnetization without an external spin polarizer.
非互惠磁传输是自旋电子学的核心课题之一，因为它对电探测磁信息非常重要。在众多用于读取磁序的电探针中，单向磁阻（UMR）是目前备受关注的一个问题，其特征是电流或磁化反向时的符号变化，并已在各种自旋轨道耦合双层系统中被发现，这些系统由一个（反）铁磁层和一个具有强自旋霍尔效应的非磁层组成。最近的一项理论研究预测，这些金属导电双层膜中的自旋反常霍尔（SAH）超导磁共振可能源于铁磁层的自旋反常霍尔效应和结构反转不对称。然而，这种类型的 UMR 还未见实验报道。在这里，我们给出了轻金属/铁磁金属铜/钴双层膜中自旋反常-霍尔 UMR 的实验证据，非平衡自旋净密度的出现归因于铜/钴界面自旋记忆损失效应和多重自旋反射导致的界面自旋泄漏不对称。我们还展示了通过改变铜的厚度在 Cu/Co/CuOx 三层中实现高度可调的 UMR，这是由于 Co/CuOx 中的轨道拉什巴效应和 Cu/Co 中的自旋反常-霍尔效应之间的竞争造成的。我们的研究拓宽了 UMR 器件应用的材料选择范围，并提供了一种无需外部自旋极化器即可检测面内磁化的替代方法。
{"title":"Spin-anomalous-Hall unidirectional magnetoresistance in light-metal/ferromagnetic-metal bilayers","authors":"QiKun Huang, Xiaotian Cui, Shun Wang, Ronghuan Xie, Lihui Bai, Yufeng Tian, Qiang Cao, Shishen Yan","doi":"10.1063/5.0194720","DOIUrl":"https://doi.org/10.1063/5.0194720","url":null,"abstract":"Nonreciprocal magnetotransport is one of the central topics in spintronics because of its importance for electrically probing magnetic information. Among numerous electrical probes used to read magnetic orders, unidirectional magnetoresistance (UMR), characterized by sign changes upon reversal of either current or magnetization, is currently a matter of great interest and has been identified in various spin–orbit-coupled bilayer systems composed of an (anti)ferromagnetic layer and a nonmagnetic layer with strong spin Hall effect. A recent theoretical work predicts that a spin-anomalous-Hall (SAH) UMR in those metallic conducting bilayers can originate from the spin-anomalous-Hall effect of the ferromagnetic layer and the structural inversion asymmetry. However, this type of UMR has not been reported experimentally. Here, we give the experimental evidence of spin-anomalous-Hall UMR in the light-metal/ferromagnetic-metal Cu/Co bilayers, where the emergence of net nonequilibrium spin density is attributed to the interfacial spin leakage asymmetry due to the spin memory loss effect at the Cu/Co interface and multiple spin reflections. We also show a highly tunable UMR in the Cu/Co/CuOx trilayer by varying the Cu thickness, which is due to the competition between the orbital Rashba effect in Co/CuOx and the spin-anomalous-Hall effect in Cu/Co. Our work widens the material choice for UMR device applications and provides an alternative approach to detect in-plane magnetization without an external spin polarizer.","PeriodicalId":8200,"journal":{"name":"Applied physics reviews","volume":"27 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2024-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141736862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ever since they have been studied, gas discharges have been classified by their visual appearance as well as by their current and voltage levels. Glow and arc discharges are the most prominent and well-known modes of discharges involving electrodes. In a first approximation, they are distinguished by their current and voltage levels, and current–voltage characteristics are a common way to display their relations. In this review, glow discharges are defined by their individual electron emission mechanism such as secondary electron emission by photons and primary ions, and arcs by their respective collective mechanism such as thermionic or explosive electron emission. Emitted electrons are accelerated in the cathode sheath and play an important role in sustaining the discharge plasma. In some cases, however, electron emission is not important for sustaining the plasma, and consequently we have neither a glow nor an arc discharge but a third type of discharge, the ohmic discharge. In part 1 of this review, these relationships are explained for quasi-stationary discharges, culminating with updated graphical presentations of I–V characteristics (Figs. 15 and 16). In part 2, further examples are reviewed to include time-dependent discharges, discharges with electron trapping (hollow cathode, E×B discharges) and active anode effects.
{"title":"Glows, arcs, ohmic discharges: An electrode-centered review on discharge modes and the transitions between them","authors":"André Anders","doi":"10.1063/5.0205274","DOIUrl":"https://doi.org/10.1063/5.0205274","url":null,"abstract":"Ever since they have been studied, gas discharges have been classified by their visual appearance as well as by their current and voltage levels. Glow and arc discharges are the most prominent and well-known modes of discharges involving electrodes. In a first approximation, they are distinguished by their current and voltage levels, and current–voltage characteristics are a common way to display their relations. In this review, glow discharges are defined by their individual electron emission mechanism such as secondary electron emission by photons and primary ions, and arcs by their respective collective mechanism such as thermionic or explosive electron emission. Emitted electrons are accelerated in the cathode sheath and play an important role in sustaining the discharge plasma. In some cases, however, electron emission is not important for sustaining the plasma, and consequently we have neither a glow nor an arc discharge but a third type of discharge, the ohmic discharge. In part 1 of this review, these relationships are explained for quasi-stationary discharges, culminating with updated graphical presentations of I–V characteristics (Figs. 15 and 16). In part 2, further examples are reviewed to include time-dependent discharges, discharges with electron trapping (hollow cathode, E×B discharges) and active anode effects.","PeriodicalId":8200,"journal":{"name":"Applied physics reviews","volume":"208 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141730557","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shan Liu, Xue Li, Li Gan, Sutong Liu, Hongzhi Luo, Xiaoxin Du, Samah A. Loutfy, Hong Tan, Jinhong Guo, Chenzhong Li
Real-time health monitoring and precision treatment are important in the biomedical field. Researchers have focused on unique gadgets with peculiar functions, which have emerged from the merging of electronic components with biological systems. Because implantable bioelectronics can sense bodily information or elicit bodily reactions in living creatures from sites outside the body, they are becoming helpful and promising remedies for a variety of ailments. Carbon materials are more suitable than other materials for the manufacture of implantable medical electronics due to their excellent biocompatibility, fatigue resistance, and low specific gravity. Therefore, carbon materials can apply to a wide range of implantable drug delivery devices, biosensors, therapeutic stimulators, and energy storage and play irreplaceable roles in neurological, cardiovascular, gastrointestinal, and locomotor systems, among others. This review aims to offer researchers insight into carbon-based implantable bioelectronics in the biomedical field. Initially, various types of carbon materials were introduced. Subsequently, it delves into carbon-based implantable bioelectronics from four perspectives: implantable actuators, biosensors, drug delivery systems, and power supplies. Furthermore, we anticipate the future direction and potential applications of carbon-based implantable bioelectronics. Given the evolving field of nanotechnology and bioelectronics, we are optimistic that these devices will foster significant breakthroughs and innovations in the biomedical sector. Ultimately, this review aims to assist researchers in navigating the choices and directions of carbon-based implantable bioelectronics, thereby promoting the advancement of the biomedical field and contributing positively to the health and welfare of humankind.
{"title":"Carbon-based implantable bioelectronics","authors":"Shan Liu, Xue Li, Li Gan, Sutong Liu, Hongzhi Luo, Xiaoxin Du, Samah A. Loutfy, Hong Tan, Jinhong Guo, Chenzhong Li","doi":"10.1063/5.0160168","DOIUrl":"https://doi.org/10.1063/5.0160168","url":null,"abstract":"Real-time health monitoring and precision treatment are important in the biomedical field. Researchers have focused on unique gadgets with peculiar functions, which have emerged from the merging of electronic components with biological systems. Because implantable bioelectronics can sense bodily information or elicit bodily reactions in living creatures from sites outside the body, they are becoming helpful and promising remedies for a variety of ailments. Carbon materials are more suitable than other materials for the manufacture of implantable medical electronics due to their excellent biocompatibility, fatigue resistance, and low specific gravity. Therefore, carbon materials can apply to a wide range of implantable drug delivery devices, biosensors, therapeutic stimulators, and energy storage and play irreplaceable roles in neurological, cardiovascular, gastrointestinal, and locomotor systems, among others. This review aims to offer researchers insight into carbon-based implantable bioelectronics in the biomedical field. Initially, various types of carbon materials were introduced. Subsequently, it delves into carbon-based implantable bioelectronics from four perspectives: implantable actuators, biosensors, drug delivery systems, and power supplies. Furthermore, we anticipate the future direction and potential applications of carbon-based implantable bioelectronics. Given the evolving field of nanotechnology and bioelectronics, we are optimistic that these devices will foster significant breakthroughs and innovations in the biomedical sector. Ultimately, this review aims to assist researchers in navigating the choices and directions of carbon-based implantable bioelectronics, thereby promoting the advancement of the biomedical field and contributing positively to the health and welfare of humankind.","PeriodicalId":8200,"journal":{"name":"Applied physics reviews","volume":"16 1","pages":""},"PeriodicalIF":15.0,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141730562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：