npj Spintronics最新文献_第2页

The mysterious magnetic ground state of Ba14MnBi11 is likely self-doped and altermagnetic Ba14MnBi11 的神秘磁基态可能是自掺杂和变磁性的

npj Spintronics Pub Date : 2024-10-26 DOI: 10.1038/s44306-024-00056-x

Po-Hao Chang, Igor I. Mazin

{"title":"The mysterious magnetic ground state of Ba14MnBi11 is likely self-doped and altermagnetic","authors":"Po-Hao Chang, Igor I. Mazin","doi":"10.1038/s44306-024-00056-x","DOIUrl":"10.1038/s44306-024-00056-x","url":null,"abstract":"Magnetism in the Zintl compound Ba14MnBi11 is rather poorly understood. Experimental claims are largely inconsistent with ab initio calculations, much beyond typical errors of the latter. We revisit this old problem, assuming that the root of the problem may be in nonstoichiometry of existing samples. Our key finding is that the magnetic ground state is indeed very susceptible to charge doping (band filling). Calculations for stoichiometric Ba14MnBi11 give a rather stable ferromagnetic metallic state, in agreement with previous publications. However, by adding exactly one electron per Mn, the system becomes semiconducting as expected, and becomes weakly antiferromagnetic (AF). On the other hand, upon small amount of hole doping, the system transitions to a special type of AF state known as altermagnetism. Furthermore, hole and electron doping-induced phase transitions result from different underlying mechanisms, influencing different exchange pathways. We propose that the inconsistency between experiment and theory is not a failure of the latter, but results from a nontrivial ramification of nonstoichiometry. The possibility of doping-stabilized altermagnetism is exciting.","PeriodicalId":501713,"journal":{"name":"npj Spintronics","volume":" ","pages":"1-7"},"PeriodicalIF":0.0,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s44306-024-00056-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142519198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Communicating with magnons 与磁石交流

npj Spintronics Pub Date : 2024-10-14 DOI: 10.1038/s44306-024-00060-1

Qiming Shao

引用次数: 0

Absence of magnetic order in RuO2: insights from μSR spectroscopy and neutron diffraction RuO2 中的磁序缺失：μSR 光谱和中子衍射的启示

npj Spintronics Pub Date : 2024-10-05 DOI: 10.1038/s44306-024-00055-y

Philipp Keßler, Laura Garcia-Gassull, Andreas Suter, Thomas Prokscha, Zaher Salman, Dmitry Khalyavin, Pascal Manuel, Fabio Orlandi, Igor I. Mazin, Roser Valentí, Simon Moser

{"title":"Absence of magnetic order in RuO2: insights from μSR spectroscopy and neutron diffraction","authors":"Philipp Keßler, Laura Garcia-Gassull, Andreas Suter, Thomas Prokscha, Zaher Salman, Dmitry Khalyavin, Pascal Manuel, Fabio Orlandi, Igor I. Mazin, Roser Valentí, Simon Moser","doi":"10.1038/s44306-024-00055-y","DOIUrl":"10.1038/s44306-024-00055-y","url":null,"abstract":"Altermagnets are a novel class of magnetic materials, where magnetic order is staggered both in coordinate and momentum space. The metallic rutile oxide RuO2, long believed to be a textbook Pauli paramagnet, recently emerged as a putative workhorse altermagnet when resonant X-ray and neutron scattering studies reported nonzero magnetic moments and long-range collinear order. While some experiments seem consistent with altermagnetism, magnetic order in RuO2 remains controversial. We show that RuO2 is nonmagnetic, both in bulk and thin film. Muon spectroscopy complemented by density-functional theory finds at most 1.14 × 10−4 μB/Ru in bulk and at most 7.5 × 10−4 μB/Ru in 11 nm epitaxial films, at our spectrometers’ detection limit, and dramatically smaller than previously reported neutron results that were used to rationalize altermagnetic behavior. Our own neutron diffraction measurements on RuO2 single crystals identify multiple scattering as the source for the false signal in earlier studies.","PeriodicalId":501713,"journal":{"name":"npj Spintronics","volume":" ","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s44306-024-00055-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142383564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Recent progress in spin-orbit torque magnetic random-access memory 自旋轨道力矩磁随机存取存储器的最新进展

npj Spintronics Pub Date : 2024-10-01 DOI: 10.1038/s44306-024-00044-1

V. D. Nguyen, S. Rao, K. Wostyn, S. Couet

引用次数: 0

Mott materials: unsuccessful metals with a bright future 莫特材料：前途光明的不成功金属

npj Spintronics Pub Date : 2024-10-01 DOI: 10.1038/s44306-024-00047-y

Alessandra Milloch, Michele Fabrizio, Claudio Giannetti

引用次数: 0

Hybrid magnon-phonon crystals 混合镁-声子晶体

npj Spintronics Pub Date : 2024-09-04 DOI: 10.1038/s44306-024-00052-1

Liyang Liao, Jiacheng Liu, Jorge Puebla, Qiming Shao, Yoshichika Otani

引用次数: 0

Spin and orbital magnetism by light in rutile altermagnets 金红石变磁体中光的自旋和轨道磁性

npj Spintronics Pub Date : 2024-09-02 DOI: 10.1038/s44306-024-00053-0

Theodoros Adamantopoulos, Maximilian Merte, Frank Freimuth, Dongwook Go, Lishu Zhang, Marjana Ležaić, Wanxiang Feng, Yugui Yao, Jairo Sinova, Libor Šmejkal, Stefan Blügel, Yuriy Mokrousov

{"title":"Spin and orbital magnetism by light in rutile altermagnets","authors":"Theodoros Adamantopoulos, Maximilian Merte, Frank Freimuth, Dongwook Go, Lishu Zhang, Marjana Ležaić, Wanxiang Feng, Yugui Yao, Jairo Sinova, Libor Šmejkal, Stefan Blügel, Yuriy Mokrousov","doi":"10.1038/s44306-024-00053-0","DOIUrl":"10.1038/s44306-024-00053-0","url":null,"abstract":"While the understanding of altermagnetism is still at a very early stage, it is expected to play a role in various fields of condensed matter research, for example spintronics, caloritronics and superconductivity. In the field of optical magnetism, it is still unclear to which extent altermagnets as a class can exhibit a distinct behavior. Here we choose RuO2, a prototype metallic altermagnet with a giant spin splitting, and CoF2, an experimentally known insulating altermagnet, to study the light-induced magnetism in rutile altermagnets from first-principles. We demonstrate that in the non-relativisic limit the allowed sublattice-resolved orbital response exhibits symmetries, imposed by altermagnetism, which lead to a drastic canting of light-induced moments. On the other hand, we find that inclusion of spin-orbit interaction enhances the overall effect drastically, introduces a significant anisotropy with respect to the light polarization and strongly suppresses the canting of induced moments. Remarkably, we observe that the moments induced by linearly-polarized laser pulses in light altermagnets can even exceed in magnitude those predicted for heavy ferromagnets exposed to circularly polarized light. By resorting to microscopic tools we interpret our results in terms of the altermagnetic spin splittings and of their reciprocal space distribution. Based on our findings, we speculate that optical excitations may provide a unique tool to switch and probe the magnetic state of rutile altermagnets.","PeriodicalId":501713,"journal":{"name":"npj Spintronics","volume":" ","pages":"1-10"},"PeriodicalIF":0.0,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s44306-024-00053-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142117952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Enhanced exchange bias in all-oxide heterostructures with cation-ordered ferrimagnetic double-perovskite 具有阳离子有序铁磁性双过氧化物的全氧化物异质结构中的增强交换偏置

npj Spintronics Pub Date : 2024-08-13 DOI: 10.1038/s44306-024-00051-2

Xiaofu Qiu, Zelin Wang, Hetian Chen, Yuhan Liang, Xiaoyu Jiang, Yujun Zhang, Jing Ma, Fangyuan Zhu, Tianxiang Nan, Zhen Chen, Di Yi

{"title":"Enhanced exchange bias in all-oxide heterostructures with cation-ordered ferrimagnetic double-perovskite","authors":"Xiaofu Qiu, Zelin Wang, Hetian Chen, Yuhan Liang, Xiaoyu Jiang, Yujun Zhang, Jing Ma, Fangyuan Zhu, Tianxiang Nan, Zhen Chen, Di Yi","doi":"10.1038/s44306-024-00051-2","DOIUrl":"10.1038/s44306-024-00051-2","url":null,"abstract":"The realization and control of exchange bias (EB) are highly desirable for spintronic applications. All-oxide heterostructures comprised of ferromagnetic and antiferromagnetic/multiferroic oxides provide an ideal platform to enable the electric-field control of EB, promising for energy-efficient memory and logic devices. However, the low block temperature (TB) and small bias field (HEB) hinder further advances towards room-temperature applications. Here, we report an alternative approach to enhance the interface-induced EB by using ferrimagnetic double-perovskite with B-site cation ordering. In heterostructures comprised of double-perovskite Sr2FeReO6 (SFRO) and LaFeO3 (LFO), a high TB (about 250 K) and large HEB are observed, which is significantly larger than the counterparts with LFO and ferromagnetic oxides. Further analysis suggests that the cation-ordering and ferrimagnetic spin structure of the double-perovskite could contribute significantly to the enhanced exchanged bias when interfacing with G-type antiferromagnets. Our results open a new avenue for developing all-oxides heterostructures for future magnetic technologies.","PeriodicalId":501713,"journal":{"name":"npj Spintronics","volume":" ","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s44306-024-00051-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141973730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Anisotropic magnetoresistance in altermagnetic MnTe 改磁锰钛中的各向异性磁阻

npj Spintronics Pub Date : 2024-08-13 DOI: 10.1038/s44306-024-00046-z

Ruben Dario Gonzalez Betancourt, Jan Zubáč, Kevin Geishendorf, Philipp Ritzinger, Barbora Růžičková, Tommy Kotte, Jakub Železný, Kamil Olejník, Gunther Springholz, Bernd Büchner, Andy Thomas, Karel Výborný, Tomas Jungwirth, Helena Reichlová, Dominik Kriegner

{"title":"Anisotropic magnetoresistance in altermagnetic MnTe","authors":"Ruben Dario Gonzalez Betancourt, Jan Zubáč, Kevin Geishendorf, Philipp Ritzinger, Barbora Růžičková, Tommy Kotte, Jakub Železný, Kamil Olejník, Gunther Springholz, Bernd Büchner, Andy Thomas, Karel Výborný, Tomas Jungwirth, Helena Reichlová, Dominik Kriegner","doi":"10.1038/s44306-024-00046-z","DOIUrl":"10.1038/s44306-024-00046-z","url":null,"abstract":"Recently, MnTe was established as an altermagnetic material that hosts spin-polarized electronic bands as well as anomalous transport effects like the anomalous Hall effect. In addition to these effects arising from altermagnetism, MnTe also hosts other magnetoresistance effects. Here, we study the manipulation of the magnetic order by an applied magnetic field and its impact on the electrical resistivity. In particular, we establish which components of anisotropic magnetoresistance are present when the magnetic order is rotated within the hexagonal basal plane. Our experimental results, which are in agreement with our symmetry analysis of the magnetotransport components, showcase the existence of an anisotropic magnetoresistance linked to both the relative orientation of current and magnetic order, as well as crystal and magnetic order. Altermagnetism is manifested as a three-fold component in the transverse magnetoresistance which arises due to the anomalous Hall effect.","PeriodicalId":501713,"journal":{"name":"npj Spintronics","volume":" ","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s44306-024-00046-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141973748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Unconventional angular dependence of spin-orbit torque-induced harmonic Hall resistance in Pt/YIG bilayers Pt/YIG 双层膜中自旋轨道转矩诱导的谐波霍尔电阻的非常规角度依赖性

npj Spintronics Pub Date : 2024-08-12 DOI: 10.1038/s44306-024-00050-3

Takayuki Shiino, Phuoc Cao Van, Jong-Guk Choi, Geunwoo Kim, Jong-Ryul Jeong, Byong-Guk Park

{"title":"Unconventional angular dependence of spin-orbit torque-induced harmonic Hall resistance in Pt/YIG bilayers","authors":"Takayuki Shiino, Phuoc Cao Van, Jong-Guk Choi, Geunwoo Kim, Jong-Ryul Jeong, Byong-Guk Park","doi":"10.1038/s44306-024-00050-3","DOIUrl":"10.1038/s44306-024-00050-3","url":null,"abstract":"Spin-orbit torque (SOT), arising from spin-orbit coupling-induced spin currents, provides efficient control of magnetization. SOT characterization involving harmonic Hall resistances is typically done in low-current regimes, distinct from high-current regimes, where SOT-induced magnetization switching occurs. In this study, we investigate azimuthal angle (ϕ)-dependent harmonic Hall resistances of a Pt/yttrium iron garnet (YIG) layer across a wide range of measurement currents. Under low-current conditions, conventional ϕ-dependent Hall resistances are observed; the first harmonic Hall resistance exhibits sin 2ϕ behavior and the second harmonic Hall resistance comprises cos ϕ and cos 3ϕ terms. Interestingly, with increasing current, higher-order angular-dependent terms become non-negligible, referring to the sin 4ϕ and sin 6ϕ terms for the first harmonic and the cos 5ϕ and cos 7ϕ terms for the second harmonic Hall resistances. We attribute this unconventional angular dependence to the nonlinear response of magnetization direction to SOT, emphasizing its relevance to understanding the magnetization dynamics during SOT-induced switching under large currents.","PeriodicalId":501713,"journal":{"name":"npj Spintronics","volume":" ","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s44306-024-00050-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141973731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0