Article
Physics, Applied
V. O. Yagovtsev, N. G. Pugach, M. Eschrig
Summary: The study investigates magnetization induced by the inverse proximity effect in a superconductor within hybrid bilayers containing a superconductor and a ferromagnetic insulator or a strongly spin-polarized ferromagnetic metal. It is conducted within a quasiclassical Green function framework, solving Usadel equations with appropriate boundary conditions for strongly spin-polarized ferromagnetic materials and presenting a comparison with recent experimental data. The study also explores the singlet to triplet conversion of superconducting correlations as a result of the proximity effect with a ferromagnet.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2021)
Article
Physics, Applied
Duo Zhao, Xiaolei Wang, Zhijie Wang, Dahai Wei
Summary: This study demonstrates the control of spin-triplet Cooper pairs in superconducting/ferromagnet heterostructures using magnetic proximity effect and spin-orbit coupling. The fabricated Co/Nb/Pt heterostructures successfully suppress the critical temperature (T (C)) and modulate the superconducting properties through independent control of spin-orbit coupling and magnetic proximity effect. These findings offer a new approach for the design of superconducting spintronics devices.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Review
Quantum Science & Technology
Ranran Cai, Igor Zutic, Wei Han
Summary: This article reviews the important research progress of superconductor/ferromagnet (SC/FM) heterostructures, including spin-triplet superconductivity, superconducting order parameter oscillation, and topological superconductivity. These heterostructures have unique physical properties, making them promising platforms for future superconducting spintronics and quantum computation applications.
ADVANCED QUANTUM TECHNOLOGIES
(2023)
Article
Physics, Applied
Hasnain Mehdi Jafri, Muhammad Sulaman, Jing Wang, Chao Yang, Xiaoming Shi, Houbing Huang
Summary: Hybrid superconductor-ferromagnet bilayer materials show sensitivity to strain, making them suitable for strain/motion sensors. These sensors are capable of retaining strain information and resetting it when needed, opening up new possibilities for device applications.
JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM
(2022)
Article
Materials Science, Multidisciplinary
Chenghao Shen, Ranran Cai, Alex Matos-Abiague, Wei Han, Jong E. Han, Igor Zutic
Summary: We explain how Rashba spin-orbit coupling can lead to a large magnetoresistance in a two-dimensional electron gas or a conventional s-wave superconductor, even with only one ferromagnet. This enhanced magnetoresistance can be nonmonotonic and change its sign with Rashba SOC. In quasi-2D van der Waals ferromagnets coupled with conventional s-wave superconductors, we observe an enhanced magnetoresistance due to the presence of Rashba SOC, which reduces the effective interfacial strength and results in equal-spin Andreev reflection, providing evidence for proximity-induced equal-spin-triplet superconductivity.
Article
Physics, Condensed Matter
Isaias G. de Oliveira, Mauro M. Doria
Summary: The spike state is a metastable vortex state that emerges and disappears at a critical field, setting the transition from normal to superconducting state. It is predicted to exist in a specific range at the mesoscopic scale, defining genuine type-I superconductors. The lifetime of the spike state is found to be affected by the geometry, with a triangular cross section having a shorter lifetime compared to a circular cross section.
PHYSICA B-CONDENSED MATTER
(2023)
Article
Materials Science, Multidisciplinary
Yiming Zhang, Xuanhao Yuan, Jian Hao, Meiling Xu, Yinwei Li
Summary: This article introduces a new method to achieve high superconductivity in borophene by assembling layered boron sheets between kagome and honeycomb boron layers. A tri-layer borophene, named hP8-B, is designed and shows high superconductivity with an estimated Tc of 35.6 K, the highest among all elemental 2D materials. The high Tc is mainly contributed by the strong coupling of sigma-bonding electrons of the kagome layers and in-plane vibrational modes. Electronic band structure calculations indicate the existence of a Dirac cone near the Fermi level, suggesting that hP8-B may be a potential topological superconductor. The superconductivity of hP8-B can be enhanced to 46.4 K under a biaxial tensile strain of 3% and doping density of 0.0375 holes per atom, due to the softening of the in-plane vibrational modes.
MATERIALS TODAY PHYSICS
(2023)
Article
Robotics
Zehao Wu, Qingsong Xu, Nana Ai, Wei Ge
Summary: This paper presents a novel magnetically actuated biaxial robot that integrates magnetic torque and force driving. The robot enables grasping, rotating, and transporting operations of the target object, achieved by electromagnetic coils and permanent magnets. Analytical models are established and the structural parameters are optimized through simulation. Experimental tests with a prototype show the robot's effectiveness in biological sample handling.
IEEE ROBOTICS AND AUTOMATION LETTERS
(2023)
Article
Physics, Applied
G. Bauer, M. Ozeri, M. S. Anwar, H. Matsuki, N. Stelmashenko, S. Yochelis, M. Cuoco, J. W. A. Robinson, Y. Paltiel, O. Millo
Summary: We studied the voltage-current characteristics of a superconductor-insulator-ferromagnet heterostructure, with pinhole-defects in the insulating layer. The superconducting layer exhibited multiple voltage jumps that were hysteric with the current sweep direction. This behavior was attributed to pinholes inducing local, distinct, coupling regions between the superconducting and ferromagnetic layers, which could potentially be used in the design of a magnetically driven superconductor memristor. Additionally, the junctions displayed absolute and differential negative resistances below the superconducting critical temperature and current, which was analyzed using a circuit approach and attributed to current passing through pinholes within the insulating layer. These unique effects stemming from the pinhole-governed interface topology could have applications in superconductor-based switches and memory devices.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2023)
Article
Physics, Applied
Martin Moeddel, Florian Griese, Tobias Kluth, Tobias Knopp
Summary: Advancements in micromachinery and nanotechnology, such as magnetically actuated microrobots for navigating in viscous environments, play a crucial role in medicine. Studies have shown that the spatial orientation of immobilized nanoparticles with parallel-aligned magnetic easy axes affects the magnetization response to an external dynamic magnetic field. This study introduces a method to estimate this orientation and experimentally investigate potential application scenarios.
PHYSICAL REVIEW APPLIED
(2021)
Article
Materials Science, Multidisciplinary
Artek R. Chalifour, Jonathon C. Davidson, Nicholas R. Anderson, Thomas M. Crawford, Karen L. Livesey
Summary: The magnetic relaxation time of single-domain nanoparticles is crucial for characterizing their properties, such as anisotropy and behavior in applied fields. Brown's famous result, although overestimating the relaxation time, is commonly used to extract nanoparticle parameters. Various analytic expressions for relaxation time do a reasonable job, as long as a full calculation for the attempt time is used instead of the commonly used estimate tau(0) around 1 ns.
Article
Materials Science, Multidisciplinary
Yiwei Liang, X. Zhang, M. Xu, G. Xu, Y. Li
Summary: Using swarm-intelligence structure prediction methodology and first-principles calculations, a ternary double-metal boron clathrate superconductor LiLaB8 with topologically protected surface states has been predicted. It can possibly be synthesized under pressures above 75 GPa and recover to ambient conditions with well-preserved cages. The enhanced superconductivity originates from the vibrations of La and B atoms, while the band inversion of La 5d and B 2p orbitals indicates its nontrivial band topology. This study provides a platform for studying fascinating phenomena arising from the interplay of superconductivity and band topology.
MATERIALS TODAY PHYSICS
(2022)
Article
Physics, Applied
William M. Strickland, Bassel Heiba Elfeky, Joseph O'Connell Yuan, William F. Schiela, Peng Yu, Dylan Langone, Maxim G. Vavilov, Vladimir E. Manucharyan, Javad Shabani
Summary: Voltage-tunable superconductor-semiconductor devices with wideband gate tunability have been demonstrated by connecting a gated InAs-Al Josephson junction to a coplanar waveguide resonator. The resonant frequency is controlled via a gate-tunable Josephson inductance and the nonlinearity of the InAs-Al junction is nondissipative. The device exhibits a high tunability, with a resonant frequency tuning range of over 2 GHz, and can strongly hybridize two resonant modes with a coupling strength of 51 MHz.
PHYSICAL REVIEW APPLIED
(2023)
Article
Physics, Multidisciplinary
Wonjune Choi, Omid Tavakol, Yong Baek Kim
Summary: The interplay of non-Fermi liquid and superconductivity, resulting from strong dynamical interactions, is studied in the context of the Yukawa-SYK model. It is found that the spin-dependent interactions prefer unconventional spin-triplet pairing, while the spin-independent interactions show instabilities in all pairing channels. Despite shortening the lifetime of fermions in the non-Fermi liquid, the interactions also enhance the tendency to pair the incoherent fermions, leading to an increased onset temperature of pairing.
Article
Physics, Applied
Lilian Prodan, Donald M. Evans, Sinead M. Griffin, Andreas Oestlin, Markus Altthaler, Erik Lysne, Irina G. Filippova, Sergiu Shova, Liviu Chioncel, Vladimir Tsurkan, Istvan Kezsmarki
Summary: We investigated the magnetic anisotropy of Fe3Sn kagome bilayer ferromagnet using bulk magnetometry and magnetic force microscopy. The magnetization dependence on the orientation of the external magnetic field showed strong easyplane magnetocrystalline anisotropy and anisotropy of the saturation magnetization. Ab initio electronic structure calculations and micromagnetic simulations agreed well with the experimental values, providing insights into the magnetic properties of Fe3Sn.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Applied
Martin Lonsky, Axel Hoffmann
Summary: This study presents comprehensive micromagnetic simulations of Synthetic antiferromagnet (SAF) nanostructures with an interfacial Dzyaloshinskii-Moriya interaction, discussing rich phase diagrams with various magnetic configurations, resonant excitations of individual skyrmions and skyrmioniums, and the internal modes of SAF skyrmion clusters in the context of magnetic sensing applications.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Andy T. Clark, X. Wang, A. R. Stuart, Q. Wang, W. Jiang, J. E. Pearson, S. G. E. te Velthuis, A. Hoffmann, X. M. Cheng, K. S. Buchanan
Summary: We report the formation of Ne ' el-type magnetic bubble skyrmions at room temperature in [Pt/Co/Ir]3 multilayered thin films after an in-plane magnetic field treatment. Micromagnetic simulations show that in-plane fields slightly below the saturation field are the most effective at producing skyrmions, and a small field angle away from the sample plane not only leads to improved skyrmion formation but also provides a means to select the skyrmion polarity.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2022)
Article
Chemistry, Physical
Joao E. F. S. Rodrigues, Javier Gainza, Federico Serrano-Sanchez, Romualdo S. Silva Jr, Catherine Dejoie, Norbert M. Nemes, Oscar J. Dura, Jose L. Martinez, Jose Antonio Alonso
Summary: In this study, Gd-filled skutterudite GdxCo4Sb12 was prepared under high pressure and moderate temperature. The structural characterization revealed a filling fraction of x = 0.033(2) and an average bond length of 3.3499(3) angstrom. The lattice thermal expansion and Debye temperature were determined, showing that the application of the harmonic Debye theory underestimates the Debye temperature in skutterudites. The presence of Gd atom contributed to an ultra-low thermal conductivity and high thermoelectric efficiency.
Article
Materials Science, Multidisciplinary
J. E. Rodrigues, A. D. Rosa, J. Lopez-Sanchez, E. Sebastiani-Tofano, N. M. Nemes, J. L. Martinez, J. A. Alonso, O. Mathon
Summary: Understanding the electronic and structural changes in nickelates with a perovskite structure is crucial for their application as industrial devices. This study focuses on PrNiO3 and investigates the structural changes at a local level using X-ray absorption spectroscopy. The results reveal the presence of different phases and the coupling behavior between spin configuration and phonons. This approach provides new opportunities for similar studies in related materials.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Crystallography
Javier Gainza, Federico Serrano-Sanchez, Joao E. F. S. Rodrigues, Oscar J. J. Dura, Brenda Fragoso, Mateus M. M. Ferrer, Norbert M. M. Nemes, Jose L. Martinez, Maria T. Fernandez-Diaz, Jose A. Alonso
Summary: Among chalcogenide thermoelectric materials, SnTe is a promising alternative to toxic PbTe for intermediate temperature applications. Pure polycrystalline SnTe was obtained by arc melting and its structural evolution was studied using temperature-dependent neutron powder diffraction (NPD) from room temperature up to 973 K. The sample exhibited a cubic crystal structure (space group Fm-3m) with pronounced displacement parameters for Te atoms. The structural analysis allowed the determination of Debye model parameters and provided insights into the Sn-Te chemical bonds. SEM images revealed nanostructuration in layers below 30 nm, contributing to a reduced thermal conductivity of 2.5 W/m center dot K at 800 K. The SPS treatment appeared to reduce Sn vacancies, resulting in decreased carrier density, increased Seebeck coefficient (up to 60 mu V K-1 at 700 K), and nearly doubled weighted mobility compared to the as-grown sample.
Article
Crystallography
Joao Elias F. S. Rodrigues, Javier Gainza, Federico Serrano-Sanchez, Norbert M. Nemes, Oscar J. Dura, Jose Luis Martinez, Jose Antonio Alonso
Summary: A novel Eu-filled skutterudite has been synthesized under high-pressure conditions, and its structure was studied by high-resolution synchrotron X-ray diffraction. The thermal conductivity of this alloy was measured to be 0.82 W m(-1) K-1, lower than that of other filled skutterudites.
ZEITSCHRIFT FUR KRISTALLOGRAPHIE-CRYSTALLINE MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Nan Tang, W. L. N. C. Liyanage, Sergio A. Montoya, Sheena Patel, Lizabeth J. Quigley, Alexander J. Grutter, Michael R. Fitzsimmons, Sunil Sinha, Julie A. Borchers, Eric E. Fullerton, Lisa DeBeer-Schmitt, Dustin A. Gilbert
Summary: Magnetic skyrmions exhibit unique behaviors arising from their topological protection, including well-defined, 3D dynamic modes at microwave frequencies. Spin waves ejected into the interstitial regions between skyrmions create a magnetic turbulent sea. However, spin-wave interference can result in ordered structures due to the well-defined length scale and ordered lattice. This study captures the dynamics in hybrid skyrmions using small-angle neutron scattering and identifies a dynamic spin-wave fractal structure.
ADVANCED MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Ilkin Goksal, Hasan Piskin, Bayram Kocaman, Kutay Akin, Dogukan Cay, Ege Selvi, Vedat Karakas, Sergi Lendinez, Hilal Saglam, Yi Li, John E. Pearson, Ralu Divan, Wei Zhang, Valentine Novosad, Axel Hoffmann, Ozhan Ozatay
Summary: This study investigates the conditions under which an ultra-thin metallic antiferromagnet becomes susceptible to spin-orbit torques. The results indicate that there is a specific range of thickness where the spins can be controlled by spin-orbit torques, while lower and higher thicknesses affect the sensitivity to spin currents. Structural changes in multilayers also quench local torques.
INTERNATIONAL JOURNAL OF APPLIED ELECTROMAGNETICS AND MECHANICS
(2023)
Article
Chemistry, Physical
Clarisse Woodahl, Sasawat Jamnuch, Angelique Amado, Can B. Uzundal, Emma Berger, Paul Manset, Yisi Zhu, Yan Li, Dillon D. Fong, Justin G. Connell, Yasuyuki Hirata, Yuya Kubota, Shigeki Owada, Kensuke Tono, Makina Yabashi, Suzanne G. E. te Velthuis, Sanja Tepavcevic, Iwao Matsuda, Walter S. Drisdell, Craig P. Schwartz, John W. Freeland, Tod A. Pascal, Alfred Zong, Michael Zuerch
Summary: Solid-state electrolytes have the potential to address safety and dendrite formation issues in lithium-ion batteries. However, the understanding of lithium dynamics in these materials is currently limited by a lack of in operando measurements. In this study, extreme-ultraviolet spectroscopy was used to investigate a solid-state electrolyte, revealing the distinctive behavior of surface lithium ions and the underlying factors contributing to interfacial resistance. These findings provide insights for the development of improved electrochemical devices through lithium-ion interfacial engineering.
Article
Physics, Applied
David Sanchez-Manzano, S. Mesoraca, F. Cuellar, M. Cabero, S. Rodriguez-Corvillo, V Rouco, F. Mompean, M. Garcia-Hernandez, J. M. Gonzalez-Calbet, C. Feuillet-Palma, N. Bergeal, J. Lesueur, C. Leon, Javier E. Villegas, J. Santamaria
Summary: The recent discovery of a long-range unconventional Josephson effect between YBa2Cu3O7 high Tc cuprates separated by a manganite ferromagnet has revealed a novel triplet proximity effect. The temperature dependence of the critical current in planar Josephson junctions was examined, and it was found that the behavior of the critical current follows the predictions of traditional superconductor-normal metal-superconductor junctions, suggesting that triplet pairs in a ferromagnet are transported similarly to singlet pairs in a normal metal. This result calls for theoretical studies of the new triplet Josephson effect and highlights its potential in future superconducting spintronics.
SUPERCONDUCTOR SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Edwin Herrera, Beilun Wu, Evan O'Leary, Alberto M. Ruiz, Miguel Agueda, Pablo Garcia Talavera, Victor Barrena, Jon Azpeitia, Carmen Munuera, Mar Garcia-Hernandez, Lin-Lin Wang, Adam Kaminski, Paul C. Canfield, Jose J. Baldovi, Isabel Guillamon, Hermann Suderow
Summary: The orthorhombic compound AuSn4 is similar to the Dirac node arc semimetal PtSn4 in composition. Unlike PtSn4, AuSn4 is a superconductor with a critical temperature of T-c = 2.35 K. Recent measurements indicate quasi-two-dimensional superconducting behavior in AuSn4.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Physics, Applied
Yi Li, Tzu-Hsiang Lo, Jinho Lim, John E. Pearson, Ralu Divan, Wei Zhang, Ulrich Welp, Wai-Kwong Kwok, Axel Hoffmann, Valentine Novosad
Summary: Researchers achieve unidirectional microwave transduction with sub-micrometer-wavelength propagating magnons in a yttrium iron garnet (YIG) thin-film delay line, obtaining non-decaying isolation of 30 dB and a broad field-tunable bandpass frequency range up to 14 GHz.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Carmen Abia, Carlos A. Lopez, Javier Gainza, Joao Elias F. S. Rodrigues, Brenda Fragoso, Mateus M. Ferrer, Norbert M. Nemes, Oscar J. Dura, Jose Luis Martinez, Maria Teresa Fernandez-Diaz, Jose Antonio Alonso
Summary: Rubidium di-tin pentabromide (RbSn2Br5) is a lead-free alternative material with high crystallinity that can be easily synthesized using a ball milling procedure. It has the potential to be used as a photovoltaic and optoelectronic material due to its improved stability and tolerance to ambient conditions. Experimental studies have shown that it has high electronic conductivity and Seebeck coefficient, as well as low thermal conductivity.
Article
Materials Science, Multidisciplinary
X. Wen, J. Pierce, N. Lavrik, S. J. Randolph, W. Guo, M. R. Fitzsimmons
Summary: The flow of the normal fluid component of He II around a cylinder and flat plate in a channel with a square crosssection was observed using He*2 excimer clouds tracking. The flow was generated by a lithographically patterned heater, and even after the heater was turned off, the direction and speed of the flow exhibited significant changes over time. High-speed movies were recorded to capture the fast movement of excimers. Velocity vector field maps indicated the formation of structures downstream of the cylinder that resembled eddies. This paper establishes a foundation for the observation of normal component flow in a quantum fluid over centimeters.
Article
Materials Science, Multidisciplinary
Surendra Singh, J. Olamit, M. R. Fitzsimmons, J. D. Thompson, H. Jeen, A. Biswas
Summary: The dynamics and interaction of different electronic phases near the metal-to-insulator transition of the phase-separated (La0.5Pr0.5)0.625Ca0.375MnO3 (LPCMO) thin film were studied. Measurements of the in-plane angle-dependent remanence and coercivity field indicate an in-plane uniaxial magnetic anisotropy for the film. The correlation between FORC measurements, resistance relaxation, and macroscopic magnetic measurements suggests a fast reversal of electronic and magnetic phases and strong interaction of different phases for the LPCMO system.
