Article
Materials Science, Multidisciplinary
Ryo Noguchi, Kenta Kuroda, Mitsuaki Kawamura, Koichiro Yaji, Ayumi Harasawa, Takushi Iimori, Shik Shin, Fumio Komori, Taisuke Ozaki, Takeshi Kondo
Summary: The study utilized laser-SARPES technology to obtain new findings on spin- and angle-resolved photoemission spectroscopy of thin films, experimentally confirming the scalability of Rashba parameters and verifying it theoretically. By revealing the proportionality between Rashba parameters and charge density at the interface, as well as the spin-orbit coupling ratio, a new approach to tuning spin splitting in 2D heterostructure systems was provided.
Article
Chemistry, Multidisciplinary
Woo Seung Ham, Thi Huynh Ho, Yoichi Shiota, Tatsuya Iino, Fuyuki Ando, Tetsuya Ikebuchi, Yoshinori Kotani, Tetsuya Nakamura, Daisuke Kan, Yuichi Shimakawa, Takahiro Moriyma, Eunji Im, Nyun-Jong Lee, Kyoung-Whan Kim, Soon Cheol Hong, Sonny H. H. Rhim, Teruo Ono, Sanghoon Kim
Summary: Spin current, converted from charge current via spin Hall or Rashba effects, can transfer its angular momentum to local moments in a ferromagnetic layer. A high charge-to-spin conversion efficiency is required for developing future memory or logic devices, and here it is demonstrated in an artificial superlattice without centrosymmetry. The observed field-like torque efficiency in the [Pt/Co/W] superlattice with sub-nm scale thickness is about 0.6 when the W thickness becomes 0.6 nm, which is significantly higher than other metallic heterostructures.
Article
Materials Science, Multidisciplinary
Lei Sun, Xikui Ma, Jian Liu, Mingwen Zhao
Summary: By using first-principles calculations and Floquet theory, we found that a significant anisotropic Rashba spin splitting can be induced in the valence and conduction bands of buckled honeycomb GaAs monolayer under specific laser irradiation conditions. This nonlinear effect, determined by the laser propagation direction, provides the possibility of controlling the anisotropy characteristics of Rashba effect and enables the generation of spin-polarized electrons for spintronic devices.
Article
Chemistry, Physical
Jiajia Chen, Kai Wu, Wei Hu, Jinlong Yang
Summary: Research shows that 2D polar perovskites have large Rashba constants and strong electric field responses, making them suitable for use in spin FETs, enabling a short spin channel length of tens of nanometers to preserve spin coherence.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Chiranjit Mondal, Chanchal K. Barman, Aftab Alam, Biswarup Pathak
Summary: The article presents a general symmetry-based mechanism to achieve intertwined giant Rashba splitting and topological nontrivial states simultaneously in a single crystalline system, supported by ab initio calculations. Significant values of Rashba parameters have been achieved in KSnSb0.625Bi0.375, surpassing those of widely studied topologically trivial Rashba semiconductor BiTeI.
Review
Chemistry, Multidisciplinary
Qikun Tian, Wenqi Zhang, Zhenzhen Qin, Guangzhao Qin
Summary: The field of thermoelectricity plays a crucial role in daily life, and the search for high-performance TE materials and effective TE optimization strategies has become increasingly important. The TE performance of Rashba-type materials is comprehensively analyzed in the article, while TE optimization strategies with Rashba spin-split show great potential in breaking through the ZT optimization bottleneck.
Article
Chemistry, Physical
Sheng Tao, Lixuan Kan, Yang Li, Xiangpeng Zhang, Yongchao Xie, Jun Tang, Xixiang Zhu, Haomiao Yu, Jinpeng Li, Kai Wang
Summary: The Bychkov-Rashba spin-orbit coupling is found to be crucial for photoinduced photoluminescence with double emissions in one-dimensional lead halide perovskite nanowires. This phenomenon, which occurs at low temperatures, is proven to be governed solely by the Rashba effect through extensive analyses. Understanding the photoluminescence characteristics of perovskite nanowires is of great significance for the development of novel nanophotonic devices.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Rongrong Xie, Panfeng Cao, Zheyuan Xu, Boyi Xu, Jinyue Fu, Xiaoli Zhu, Xianwei Fu, Sheng-Yi Xie, Ying Jiang, Anlian Pan
Summary: This study reports a significant out-of-plane spin polarization in the two-dimensional Dion-Jacobson (DJ) perovskite, which is the physical origin of the large Rashba spin splitting observed. The generation of this unconventional spin component indicates the significant influence of the in-plane asymmetric crystal field on the spin-orbit interactions. These results suggest that the studied system may serve as a type of spin source material to explore the attractive out-of-plane spin polarization.
Article
Materials Science, Multidisciplinary
Ghulam Hussain, Abdus Samad, Majeed Ur Rehman, Giuseppe Cuono, Carmine Autieri
Summary: First-principles calculations are used to study the structural stability and spintronics properties of Janus MoGeSiP2As2 and WGeSiP2As2 monolayers. The results show that these structures have high cohesive energies, stable phonon modes, reduced direct bandgaps, and large spin-split states. Breaking the mirror symmetry in the Janus monolayer structures leads to spin splitting.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Hongze Deng, Chenhui Zhang, Weizheng Liang, Xi-Xiang Zhang, Sheng-Nian Luo
Summary: In this study, the decay dynamics of hot carriers in a noncentrosymmetric semiconductor BiTeI with large spin-orbit splitting were investigated using time-resolved ultrafast optical spectroscopy. By tuning the pump photon energy, the decay behaviors of hot carriers in different energy bands were observed.
Article
Chemistry, Physical
Preeti Bhumla, Deepika Gill, Sajjan Sheoran, Saswata Bhattacharya
Summary: Spin-orbit coupling plays a key role in several intriguing quantum phenomena, including the Rashba-Dresselhaus effect. By studying the lead halide perovskite CsPbF3, researchers have discovered potential applications in spintronics, with tunable Rashba spin splitting and reversible spin textures observed. The findings suggest promising opportunities for perovskite-based spintronic devices.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Physics, Multidisciplinary
Shuai Zhang, Fei Wang, Bin Cui, Chong Li, Yu Jia
Summary: The Rashba spin splitting of monovalent alkali metal adsorbed on Au/Si(111) surface is explained using first-principles calculations and analyses. It is found that Na adatom donates one electron to the pristine surface, leading to a large Rashba spin splitting in Na/Au/Si(111) system. Cs adsorbate, with larger intra-atomic spin-orbit coupling, not only plays the same role as Na adatom but also induces intrinsic spin-polarization, further enhancing the Rashba spin splitting on the Cs/Au/Si(111) surface. The proposed mechanism of intrinsic spin-polarization significantly enhancing the Rashba spin splitting is generally applicable and can be extended to alkali-earth metal epitaxial layers on Au/Si(111) surface.
Article
Materials Science, Multidisciplinary
L. L. Tao, Jiayu Li, Yuntian Liu, Xianjie Wang, Yu Sui, Bo Song, M. Ye. Zhuravlev, Qihang Liu
Summary: This article investigates the Rashba spin splitting phenomenon around non-time-reversal-invariant momenta and elucidates its microscopic origin. It is found that certain Bloch wave functions in specific non-invariant momentum regions can eliminate the first-order spin-orbit coupling effect, resulting in a tiny spin-orbit gap and helical spin texture. Furthermore, this quasi-symmetry-induced tiny gap can exhibit large Berry curvature, making it desirable for various topological applications. The study expands the concept of Rashba physics and paves the way for designing novel spin-splitting materials through the cooperation of symmetry and orbital engineering.
Article
Materials Science, Multidisciplinary
Yang Wang, Binbin Liu, Yue-Xin Huang, Sivakumar Mambakkam, Yong Wang, Shengyuan A. Yang, Xian-Lei Sheng, Stephanie A. Law, John Q. Xiao
Summary: In addition to the topologically protected linear dispersion, a tunable Rashba spin-splitting two-dimensional electron gas was found on the surface of topological insulators. Large bilinear magnetoresistance was observed in Bi2Se3 films decorated with transition-metal atoms, and this effect can be fine tuned through surface atom deposition for potential spintronic applications.
Article
Physics, Condensed Matter
Xiujuan Mao, Jia Li, Ze Liu, Jiaxi Wang, Fuli He, Yafan Wang
Summary: Based on first-principles calculations, the coexistence of unconventional Rashba- and Zeeman-type spin splitting is observed in the Pb-adsorbed monolayer WSe2 system. The spin splitting properties can be effectively regulated by adjusting the adsorption configuration and distance. This predicted adsorption system shows promise for spintronic applications.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Physics, Multidisciplinary
Juraj Krempasky, Laurent Nicolai, Martin Gmitra, Houke Chen, Mauro Fanciulli, Eduardo B. Guedes, Marco Caputo, Milan Radovic, Valentine V. Volobuev, Ondrej Caha, Gunther Springholz, Jan Minar, J. Hugo Dil
Summary: The study reveals that ferroelectric alpha-GeTe exhibits a multiple nontrivial topology of the electronic band structure, with the presence of triple-points and type-II Weyl fermions. Using spin- and angle-resolved photoemission spectroscopy combined with density functional theory, the research uncovers the unique spin texture around the triple point caused by the crossing of spin-degenerate and spin-split bands.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Shiming Lei, Samuel M. L. Teicher, Andreas Topp, Kehan Cai, Jingjing Lin, Guangming Cheng, Tyger H. Salters, Fanny Rodolakis, Jessica L. McChesney, Saul Lapidus, Nan Yao, Maxim Krivenkov, Dmitry Marchenko, Andrei Varykhalov, Christian R. Ast, Roberto Car, Jennifer Cano, Maia G. Vergniory, N. Phuan Ong, Leslie M. Schoop
Summary: New developments in the field of topological matter are often driven by materials discovery, but many topological materials still suffer from non-ideal band structures. Introducing a new mechanism to design ideal Dirac semimetals, the nearly ideal Dirac semimetal GdSb0.46Te1.48 exhibits highly unusual transport behavior.
ADVANCED MATERIALS
(2021)
Article
Multidisciplinary Sciences
J. -Z. Ma, Q. -S. Wu, M. Song, S. -N. Zhang, E. B. Guedes, S. A. Ekahana, M. Krivenkov, M. Y. Yao, S. -Y. Gao, W. -H. Fan, T. Qian, H. Ding, N. C. Plumb, M. Radovic, J. H. Dil, Y. -M. Xiong, K. Manna, C. Felser, O. V. Yazyev, M. Shi
Summary: In PtGa, an experimentally observed singular Weyl point emerges at the center of the Brillouin zone, surrounded by closed Weyl nodal walls at the zone boundaries, without any Fermi arc connecting its surface projection. These findings demonstrate the emergence of nontrivial band crossings with different dimensionalities in condensed matter, expanding the scope of the Nielsen-Ninomiya no-go theorem.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Eduardo B. Guedes, Stefan Muff, Walber H. Brito, Marco Caputo, Hang Li, Nicholas C. Plumb, J. Hugo Dil, Milan Radovic
Summary: This study investigates the evolution of the electronic structure of a 2-dimensional electron gas (2DEG) on SrTiO3 surfaces, showing a metal-insulator transition around 135 K caused by local structure relaxations. The research presents a new method of tuning the 2DEG via surface vicinality and explores how prospective devices will respond to temperature changes through experimental and theoretical comparisons.
Article
Materials Science, Coatings & Films
Eduardo Bonini Guedes, Tobias Willemoes Jensen, Muntaser Naamneh, Alla Chikina, Ramus T. Dahm, Shinhee Yun, Francesco M. Chiabrera, Nicholas C. Plumb, J. Hugo Dil, Ming Shi, Dennis Valbjorn Christensen, Walber Hugo Brito, Nini Pryds, Milan Radovic
Summary: By combining experimental observations and theoretical calculations, this study investigates the surface electronic structure of bent SrTiO3 wafers. It is found that even a small external strain of 0.1% can alter the energy of in-gap states. Furthermore, calculations show that larger strain values significantly affect the orbital splitting of the surface conduction band. This research highlights the ability of strain to tailor the electronic properties of STO surfaces and interfaces.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2022)
Article
Instruments & Instrumentation
Robert Drost, Maximilian Uhl, Piotr Kot, Janis Siebrecht, Alexander Schmid, Jonas Merkt, Stefan Wunsch, Michael Siegel, Oliver Kieler, Reinhold Kleiner, Christian R. Ast
Summary: The article introduces a technique called electron spin resonance scanning tunneling microscopy (ESR-STM) that is capable of manipulating and detecting individual quantum spins under high-temperature and high-magnetic-field conditions. By overcoming challenges in signal delivery, the operational frequency range of ESR-STM has been extended to 100 GHz, enabling the study of spin dynamics in the high-field limit.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2022)
Article
Green & Sustainable Science & Technology
Remy Petremand, Guillaume Suarez, Sophie Besancon, J. Hugo Dil, Irina Guseva Canu
Summary: A Bayesian spline model was developed to analyze real-time mass concentrations of particulate matter in the personal breathing zone of Parisian subway workers. The study found differences in particle concentrations and variations at different subway stations and work areas, as well as discrepancies between different measurement methods.
Article
Physics, Multidisciplinary
Sujoy Karan, Haonan Huang, Ciprian Padurariu, Bjoern Kubala, Andreas Theiler, Annica M. Black-Schaffer, Gonzalo Morras, Alfredo Levy Yeyati, Juan Carlos Cuevas, Joachim Ankerhold, Klaus Kern, Christian R. Ast
Summary: This study demonstrates the reversal of supercurrent flow from 0 to pi in a Josephson junction by continuously changing the impurity-superconductor coupling at the atomic scale.
Article
Multidisciplinary Sciences
Juraj Krempasky, Gunther Springholz, Sunil Wilfred D'Souza, Ondrej Caha, Martin Gmitra, Andreas Ney, C. A. F. Vaz, Cinthia Piamonteze, Mauro Fanciulli, Dominik Kriegner, Jonas A. Krieger, Thomas Prokscha, Zaher Salman, Jan Minar, J. Hugo Dil
Summary: The interplay between spin-orbit interaction and magnetic order is actively studied in condensed matter physics. In this study, researchers report unique and unexpected observations in thin multiferroic Ge1-xMnxTe films, including the ability to switch the ferrimagnetic order with small currents and the coherent spread of magnetic order.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Piotr Kot, Maneesha Ismail, Robert Drost, Janis Siebrecht, Haonan Huang, Christian R. Ast
Summary: Electric control of spin resonance transitions in single TiH molecules is achieved using electron spin resonance scanning tunneling microscopy (ESR-STM). The ESR signal shows significant bias voltage dependent shifts, about ten times its line width, attributed to the electric field in the tunnel junction. The electric field induces a displacement of the spin system, changing the g-factor and the effective magnetic field of the tip. Direct electric control of spin transitions in coupled TiH dimers is demonstrated.
NATURE COMMUNICATIONS
(2023)
Article
Physics, Multidisciplinary
Haonan Huang, Sujoy Karan, Ciprian Padurariu, Bjoern Kubala, Juan Carlos Cuevas, Joachim Ankerhold, Klaus Kern, Christian R. Ast
Summary: Quantum magnetic impurities have attracted tremendous research interest due to the wealth of phenomena they give rise to. The Kondo effect is generated on a normal metal by magnetic impurities, while bound states called Yu-Shiba-Rusinov (YSR) states emerge on a superconductor. Theoretical studies have successfully unified the Kondo and YSR physics using numerical renormalization group (NRG) theory, showing that the normalized YSR energy scales universally with the Kondo temperature divided by the superconducting gap. However, experimental extraction of the Kondo temperature usually involves significant uncertainties and cannot properly account for magnetic fields. In this study, scanning tunneling microscopy and NRG are employed to accurately fit the Kondo spectra in magnetic fields and unambiguously extract the corresponding Kondo temperature.
COMMUNICATIONS PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Jacob Senkpiel, Robert Drost, Jan C. Kloeckner, Markus Etzkorn, Joachim Ankerhold, Juan Carlos Cuevas, Fabian Pauly, Klaus Kern, Christian R. Ast
Summary: In this study, a new method of continuously extracting the transport channel transmissions of atomic scale junctions using superconducting excess current is introduced. Combined with ab initio simulations, this technique is applied to determine the impact of adjacent structures on the transport properties in atomic aluminum junctions.
Review
Physics, Multidisciplinary
R. Di Capua, M. Verma, M. Radovic, N. C. Plumb, J. H. Dil, E. B. Guedes, G. M. De Luca, D. Preziosi, Z. Wang, A. P. Weber, R. Pentcheva, M. Salluzzo, Z. Ristie
Summary: Experimental and theoretical studies have shown that ferromagnetic EuTiO3 hosts a quasi-two-dimensional electron gas (q2DEG) with spin polarization at its surface, induced by oxygen vacancies. This suggests EuTiO3 as a new material platform for oxide q2DEGs characterized by broken inversion and time-reversal symmetries.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Physics, Multidisciplinary
V. N. Petrov, P. G. Gabdullin, A. Pavlov, A. B. Ustinov, V. N. Strocov, J. H. Dil
Summary: This paper describes a new spin detector designed and manufactured at SPbPU, which can analyze the polarization of the secondary electron flux while conserving information about the electrons' spatial distribution. The stages of development, construction, and testing of the detector are discussed in detail, demonstrating the feasibility of implementing such devices with high spatial resolution and efficiency. Combining these detectors with hemispherical energy analyzers will allow for obtaining spin-resolved dispersion images of the structure under study.
ST PETERSBURG POLYTECHNIC UNIVERSITY JOURNAL-PHYSICS AND MATHEMATICS
(2021)
Article
Physics, Multidisciplinary
Haonan Huang, Jacob Senkpiel, Ciprian Padurariu, Robert Drost, Alberto Villas, Raffael L. Klees, Alfredo Levy Yeyati, Juan Carlos Cuevas, Bjorn Kubala, Joachim Ankerhold, Klaus Kern, Christian R. Ast
Summary: Magnetic impurities on superconductors induce discrete bound levels called Yu-Shiba-Rusinov (YSR) states, which are fully spin polarized. By using scanning tunneling spectroscopy, the spin dynamics in the tunneling process between two YSR states were resolved, with experimentally extracted angle between spins down to 7 mK, revealing purely paramagnetic nature of the impurities. Noncollinear spin alignment is crucial for producing Majorana bound states and manipulating the Majorana state onto the tip.
PHYSICAL REVIEW RESEARCH
(2021)
