Physical Review Materials最新文献

{"title":"Dual diffraction bands of heliconical liquid crystal gratings","authors":"Sha Liu, Hao Yu, Miao Jiang, Ling-Ling Ma, Yan-Qing Lu, Qi-Huo Wei","doi":"10.1103/physrevmaterials.8.085201","DOIUrl":"https://doi.org/10.1103/physrevmaterials.8.085201","url":null,"abstract":"Gratings composed of cholesteric liquid crystals as an important optical element for emerging applications such as augmented and virtual reality and are renowned for their characteristic single reflective diffraction band. Heliconical liquid crystal is a newly discovered state where the constituent molecules self-organize into helical structures with a non-90° polar angle between the director and the helical axis. Here, we present a numerical study on the reflective diffraction of gratings made of heliconical liquid crystals. Remarkably, numerical results demonstrate that there exist two diffraction bands at the same diffraction angle, with one peak wavelength being twice the other. We show that the short-wavelength diffraction originates from the Pancharatnam-Berry phase acquired by the reflected light while the long-wavelength diffraction stems from the reflection of the slanted volume grating, and that the wavelengths of these two diffraction bands can be attributed to the first and second band gaps of the slanted volume grating as a one-dimensional photonic crystal. We further show that the polarization of the reflected diffraction light is circular, exhibiting the same handedness as the liquid crystal for the short-wavelength band, whereas it is perfectly linearly polarized along the grating direction for the long-wavelength band.","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"5 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142226380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vacancy-mediated transport and segregation tendencies of solutes in fcc nickel under diffusional creep: A density functional theory study","authors":"Shehab Shousha, Sourabh Bhagwan Kadambi, Benjamin Beeler, Boopathy Kombaiah","doi":"10.1103/physrevmaterials.8.083605","DOIUrl":"https://doi.org/10.1103/physrevmaterials.8.083605","url":null,"abstract":"The Nabarro-Herring (NH) diffusional creep theory postulates the vacancy-mediated transport of atoms under a stress gradient as the creep mechanism under low-stress and high-temperature conditions. In multicomponent alloys, we premise that this stress-assisted flow of vacancies to and from grain boundaries will produce elemental segregation. An observation of such segregation, validated with theoretical predictions, can provide the necessary experimental evidence for the occurrence of NH creep. Theoretical calculations of the segregation tendencies via analyzing the dominant solute diffusion mechanisms and the difference in diffusivities of the elements are therefore essential. To this end, this study applies density functional theory calculations of migration barriers and solute-vacancy binding energies as input to the self-consistent mean-field theory to assess the vacancy-mediated diffusion mechanisms, transport coefficients, and segregation tendencies of Co, Cr, Mo, Re, Ta, and W solutes in face-centered-cubic Ni. We find Co, Re, and W to be slow diffusers at high temperatures and Cr, Mo, and Ta to be fast diffusers. Further analysis shows that the slow diffusers tend to always enrich at vacancy sinks over a wide range of temperatures. In contrast, the fast diffusers show a transition from depletion to enrichment as the temperature lowers. Furthermore, our analysis of the segregation tendencies under tensile hydrostatic strains shows that slow diffusers are largely unaffected by the strain and favor enrichment. On the other hand, the fast diffusers exhibit high sensitivity to strain and their segregation tendency can transition from depletion to enrichment at a given temperature. The transport coefficients calculated in this work are expected to serve as input to mesoscale microstructure models to provide a more rigorous assessment of solute segregation under NH creep conditions.","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"28 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical regularization","authors":"Himangsu Bhaumik, Daniel Hexner","doi":"10.1103/physrevmaterials.8.l082601","DOIUrl":"https://doi.org/10.1103/physrevmaterials.8.l082601","url":null,"abstract":"Training materials through periodic drive allows us to endow materials and structures with complex elastic functions. As a result of the driving, the system explores the high-dimensional space of structures, ultimately converging to a structure with the desired response. However, increasing the complexity of the desired response results in ultraslow convergence and degradation. Here, we show that by constraining the search space, we are able to increase robustness, extend the maximal capacity, train responses that previously did not converge, and in some cases accelerate convergence by many orders of magnitude. We identify the geometrical constraints that prevent the formation of spurious low-frequency modes, which are responsible for failure. We argue that these constraints are analogous to regularization used in machine learning. We propose a unified relationship between complexity, degradation, convergence, and robustness.","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"30 11 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tuning intrinsic anomalous Hall effect from large to zero in two ferromagnetic states of SmMn2Ge2","authors":"Mahima Singh, Jyotirmoy Sau, Banik Rai, Arunanshu Panda, Manoranjan Kumar, Nitesh Kumar","doi":"10.1103/physrevmaterials.8.084201","DOIUrl":"https://doi.org/10.1103/physrevmaterials.8.084201","url":null,"abstract":"The intrinsic anomalous Hall conductivity (AHC) in a ferromagnetic metal is completely determined by its band structure. Since the spin orientation direction is an important band–structure tuning parameter, it is highly desirable to study the anomalous Hall effect in a system with multiple spin reorientation transitions. We study a layered tetragonal room temperature ferromagnet <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>Sm</mi><msub><mi>Mn</mi><mn>2</mn></msub><msub><mi>Ge</mi><mn>2</mn></msub></mrow></math>, which gives us the opportunity to measure magnetotransport properties where the long <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>c</mi></math>-axis and the short <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>a</mi></math>-axis can both be magnetically easy axes depending on the temperature range we choose. We show a moderately large fully intrinsic AHC up to room temperature when the crystal is magnetized along the <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>c</mi></math>-axis. Interestingly, the AHC can be tuned to completely extrinsic with extremely large values when the crystal is magnetized along the <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>a</mi></math>-axis, regardless of whether the <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>a</mi></math>-axis is magnetically easy or hard axis. First-principles calculations show that nodal line states originate from Mn-<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>d</mi></math> orbitals just below the Fermi energy (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>E</mi><mi mathvariant=\"normal\">F</mi></msub></math>) in the electronic band structure when the spins are oriented along the <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>c</mi></math>-axis. Intrinsic AHC originates from the Berry curvature effect of the gapped nodal lines in the presence of spin-orbit coupling. AHC almost disappears when the spins are aligned along the <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>a</mi></math>-axis because the nodal line states shift above <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>E</mi><mi mathvariant=\"normal\">F</mi></msub></math> and become unoccupied. Since the AHC can be tuned from fully extrinsic to intrinsic even at 300 K, <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>Sm</mi><msub><mi>Mn</mi><mn>2</mn></msub><msub><mi>Ge</mi><mn>2</mn></msub></mrow></math> becomes a potential candidate for room-temperature spintronics applications.","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"9 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Néel vector waves in antiferromagnetic CuMnAs excited by surface acoustic waves","authors":"M. Waqas Khaliq, Oliver J. Amin, Alberto Hernández-Mínguez, Marc Rovirola, Blai Casals, Khalid Omari, Sandra Ruiz-Gómez, Simone Finizio, Richard P. Campion, Kevin W. Edmonds, Vít Novák, Anna Mandziak, Lucia Aballe, Miguel Angel Niño, Joan Manel Hernàndez, Peter Wadley, Ferran Macià, Michael Foerster","doi":"10.1103/physrevmaterials.8.084406","DOIUrl":"https://doi.org/10.1103/physrevmaterials.8.084406","url":null,"abstract":"Magnetoelastic effects in antiferromagnetic CuMnAs are investigated by applying dynamic strain in the 0.01% range through surface acoustic waves in the GaAs substrate. The magnetic state of the CuMnAs/GaAs is characterized by a multitude of submicron-sized domains, which we image by x-ray magnetic linear dichroism combined with photoemission electron microscopy. Within the explored strain range, CuMnAs shows magnetoelastic effects in the form of Néel vector waves with micrometer wavelength, which corresponds to an averaged overall spin-axis rotation up to <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mn>2</mn><mo>.</mo><msup><mn>4</mn><mo>∘</mo></msup></mrow></math> driven by the time-dependent strain from the surface acoustic wave. Measurements at different temperatures indicate a reduction of the wave amplitude when lowering the temperature. However, no domain wall motion has been detected on the nanosecond timescale.","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"180 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strong correlation between ionic bonding strength and superconductivity in compressed hydrides","authors":"Xing Li, Zixuan Guo, Yansun Yao, Xiaohua Zhang, Shicong Ding, Guochun Yang","doi":"10.1103/physrevmaterials.8.084805","DOIUrl":"https://doi.org/10.1103/physrevmaterials.8.084805","url":null,"abstract":"Understanding the superconductivity in relation to chemical bonding is essential for the development of superconductors. We propose that pressure-reduced ionic bonding strength is beneficial for improving superconductivity in hydrides (negative correlation between bonding strength and critical temperature). We model ionic hydrides using a prototypical ionic lattice (CsCl-type) with simple-valence metal Li/Rb and hydrogen and control the bonding strength via external pressure. First-principles calculations reveal that the ionic bonding strength in LiH increases with pressure while its critical temperature (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>T</mi><mi mathvariant=\"normal\">c</mi></msub></math>) simultaneously decreases. A higher <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>T</mi><mi mathvariant=\"normal\">c</mi></msub></math> at lower pressures is attributed to stronger electron-phonon coupling (EPC) induced by weaker ionic bonds and significant EPC contributions from mid-frequency phonons. RbH's pressure dependences of bonding strength and <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>T</mi><mi mathvariant=\"normal\">c</mi></msub></math> are the reverse of those of LiH, and the EPC primarily results from high-frequency phonons. The distinct interorbital electron transition mechanism and amounts of charge transfer are responsible for the opposite trend of changes in bonding strength and superconductivity in LiH and RbH. The proposed correlation is further validated by the other six ionic hydrides. Substantial <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>T</mi><mi mathvariant=\"normal\">c</mi></msub></math> change (e.g., 126.2 K at 100 GPa and 5.7 K at 300 GPa in LiH) in response to bonding strength variation reveals a key factor for designing new superconductors.","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"25 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multiferroic ScLaX2 (X=P, As, and Sb) monolayers: Bidirectional negative Poisson's ratio effects and phase transformations driven by rare-earth (main-group) elements","authors":"Xinyu Tian, Xiao Xie, Jia Li, Xiangru Kong, Wei-Jiang Gong, François M. Peeters, Linyang Li","doi":"10.1103/physrevmaterials.8.084407","DOIUrl":"https://doi.org/10.1103/physrevmaterials.8.084407","url":null,"abstract":"The combination of auxetic property, ferroelasticity, and ferroelectricity in two-dimensional materials offers new avenues for next-generation multifunctional devices. However, two-dimensional materials that simultaneously exhibit those properties are rarely reported. Here, we present a class of two-dimensional Janus-like structures <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>ScLa</mi><msub><mi>X</mi><mn>2</mn></msub></mrow></math> (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>X</mi><mo>=</mo><mi mathvariant=\"normal\">P</mi></mrow></math>, As, and Sb) with a rectangular lattice based on first-principles calculations. We predict that those <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>ScLa</mi><msub><mi>X</mi><mn>2</mn></msub></mrow></math> monolayers are stable semiconductors with both intrinsic in-plane and out-of-plane auxetic properties, showing a bidirectional negative Poisson's ratio effect. The value of the out-of-plane negative Poisson's ratio effect can reach −2.28/−3.06/−3.89. By applying uniaxial strain engineering, two transition paths can be found, including the VA main group element path and the rare-earth metal element path, corresponding to the ferroelastic and the multiferroic (ferroelastic and ferroelectric) phase transition, respectively. For the <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>ScLaS</mi><msub><mi mathvariant=\"normal\">b</mi><mn>2</mn></msub></mrow></math> monolayer, the external force field can not only control the ferroelastic phase transition, but it can also lead to the reversal of the out-of-plane polarization, exhibiting potential multiferroicity. The coupling between the bidirectional negative Poisson's ratio effect and multiferroicity makes the <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>ScLa</mi><msub><mi>X</mi><mn>2</mn></msub></mrow></math> monolayers promising for future device applications.","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"71 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Absence of hydrogen insertion into highly crystalline superconducting infinite layer nickelates","authors":"M. Gonzalez, A. Ievlev, K. Lee, W. Kim, Y. Yu, J. Fowlie, H. Y. Hwang","doi":"10.1103/physrevmaterials.8.084804","DOIUrl":"https://doi.org/10.1103/physrevmaterials.8.084804","url":null,"abstract":"The discovery of superconductivity in the infinite layer nickelates introduced a materials system analogous to the cuprates for the study of unconventional superconductivity. The synthesis of infinite layer nickelates, (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>RNiO</mi><mn>2</mn></msub></math>, R = lanthanide) often uses calcium hydride (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>CaH</mi><mn>2</mn></msub></math>) to facilitate the deintercalation of apical site oxygen atoms from a precursor perovskite (<math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>RNiO</mi><mn>3</mn></msub></math>) phase via topotactic reduction. However, it remains uncertain whether the use of <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>CaH</mi><mn>2</mn></msub></math> results in the insertion of hydrogen into the infinite layer structure, and if it does, what the implications are for superconductivity. To quantify the hydrogen composition of highly crystalline infinite layer nickelates, we synthesized <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><msub><mi>Nd</mi><mrow><mn>1</mn><mo>−</mo><mi>x</mi></mrow></msub><msub><mi>Sr</mi><mi>x</mi></msub><msub><mi>NiO</mi><mn>2</mn></msub></mrow></math> thin films on LSAT substrates and conducted time-of-flight secondary ion mass spectroscopy measurements to generate hydrogen depth profiles. We compare the hydrogen density of nickelates prepared with and without a <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>SrTiO</mi><mn>3</mn></msub></math> capping layer. Additionally, we measure the hydrogen content in nickelate samples at various doping levels spanning the superconducting phase space, including the underdoped, optimally doped, and overdoped regime. We report no significant increase in hydrogen density between the perovskite and infinite layer phases in any of the measured samples. Furthermore, we put an upperbound on the hydrogen concentration of our nickelate samples to <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><msub><mi>Nd</mi><mrow><mn>1</mn><mo>−</mo><mi>x</mi></mrow></msub><msub><mi>Sr</mi><mi>x</mi></msub><msub><mi>NiO</mi><mn>2</mn></msub><msub><mi mathvariant=\"normal\">H</mi><mrow><mn>0.05</mn></mrow></msub></mrow></math>. Our results imply that hydrogen is not responsible for the emergence of superconductivity in the infinite layer nickelates.","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"4 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chemical reaction mechanisms of solid state ammonia and hydrogen under high pressure","authors":"Junyi Miao, Shi He, Kaihua He, Kewei Ding, Wei Dai, Cheng Lu","doi":"10.1103/physrevmaterials.8.083604","DOIUrl":"https://doi.org/10.1103/physrevmaterials.8.083604","url":null,"abstract":"Ammonia is the most stable compound of nitrogen and hydrogen at ambient pressure. However, the chemical reaction of nitrogen and hydrogen is more complex and difficult to explore at high pressures. Here, we have performed extensively structural searches of ammonia-hydrogen compounds based on particle swarm optimization algorithms and first principles calculations. The calculated results show that the main reaction products of nitrogen and hydrogen under high pressure can be divided into two categories: high-energy density material (HEDM) and hydrogen storage material (HSM). Three different phases of <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>NH</mi><mn>4</mn></msub></math> are potential HEDMs, which are found to be stable or metastable at 40 GPa to 300 GPa, and metastable at ambient pressure with energy density of about <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mn>2.15</mn><mspace width=\"0.28em\"></mspace><mi>kJ</mi><mo>/</mo><mi mathvariant=\"normal\">g</mi><mo>∼</mo><mn>3.86</mn><mspace width=\"0.28em\"></mspace><mi>kJ</mi><mo>/</mo><mi mathvariant=\"normal\">g</mi></mrow></math>. The <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>P</mi><mi>m</mi></mrow></math> phase of <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><msub><mi>NH</mi><mn>10</mn></msub></math> is an outstanding HSM with ultrahigh hydrogen storage (41.7 wt%) and release (29.2 wt%) capacities. These findings offer significant insights into the structural arrangements and chemical bonding patterns of ammonia-hydrogen compounds at high pressure, and suggest potential experimental avenues for elucidating how diverse metastable structures with distinct properties might be existed in planetary interiors.","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"27 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Boundary-induced phase in epitaxial iron layers","authors":"Anna L. Ravensburg, Mirosław Werwiński, Justyna Rychły-Gruszecka, Justyn Snarski-Adamski, Anna Elsukova, Per O. Å. Persson, Ján Rusz, Rimantas Brucas, Björgvin Hjörvarsson, Peter Svedlindh, Gunnar K. Pálsson, Vassilios Kapaklis","doi":"10.1103/physrevmaterials.8.l081401","DOIUrl":"https://doi.org/10.1103/physrevmaterials.8.l081401","url":null,"abstract":"We report on the discovery of a boundary-induced body-centered tetragonal iron phase in thin films deposited on <math xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><msub><mi>MgAl</mi><mn>2</mn></msub><msub><mi mathvariant=\"normal\">O</mi><mn>4</mn></msub></mrow></math> (001) substrates. We present evidence for this phase using detailed x-ray analysis and <i>ab initio</i> density functional theory calculations. A lower magnetic moment and a rotation of the easy magnetization direction are observed, as compared with body-centered cubic iron. Our findings expand the range of known crystal and magnetic phases of iron, providing valuable insights for the development of heterostructure devices using ultrathin iron layers.","PeriodicalId":20545,"journal":{"name":"Physical Review Materials","volume":"5 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142206173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}