Article
Materials Science, Multidisciplinary
Yingying Peng, Leonardo Martinelli, Qizhi Li, Matteo Rossi, Matteo Mitrano, Riccardo Arpaia, Marco Moretti Sala, Qiang Gao, Xuefei Guo, Gabriella Maria De Luca, Andrew Walters, Abhishek Nag, Andi Barbour, Genda Gu, Jonathan Pelliciari, Nicholas B. Brookes, Peter Abbamonte, Marco Salluzzo, Xingjiang Zhou, Ke-Jin Zhou, Valentina Bisogni, Lucio Braicovich, Steven Johnston, Giacomo Ghiringhelli
Summary: This study investigates the electron-phonon coupling in high-Tc superconducting cuprates using resonant inelastic x-ray scattering. By comparing the results from two cuprate families at different doping levels, it is found that the EPC strength decreases with doping and shows a nonmonotonic trend at smaller momenta, which is attributed to the screening effect of charge carriers.
Article
Materials Science, Multidisciplinary
Seung-Ho Baek, Sergey L. Bud'ko, Paul C. Canfield, F. Borsa, Byoung Jin Suh
Summary: By measuring the NMR spectra in LaAgSb2, we observed a charge-density-wave (CDW) transition at T-CDW1, which is driven by electronic instability near the Fermi level.
Article
Materials Science, Multidisciplinary
Robert J. Koch, Niraj Aryal, Oleh Ivashko, Yu Liu, Milinda Abeykoon, Eric D. Bauer, Martin V. Zimmermann, Weiguo Yin, Cedomir Petrovic, Emil S. Bozin
Summary: This study reports on a high-temperature local symmetry breaking phenomenon in binary ruthenium pnictides and analyzes its correlation with superconductivity. It is found that local distortions exist in the pseudogap regime, and these distortions are significantly enhanced when the nonmagnetic ground state is established. These findings may play an important role in the emergence of superconductivity.
Article
Astronomy & Astrophysics
A. Alonso-Izquierdo, C. Garzon Sanchez
Summary: In this paper, all defect-type solutions in a family of scalar field theories in (1+1)-dimensional Minkowski spacetime with a real and a complex field have been analytically identified. Three types of solutions have been found: (a) topological kinks without Q-balls, (b) defects consisting of a topological kink coupled with a Q-ball, and (c) a one-parameter family of solutions where a Q-ball is combined with a nontopological soliton. The properties of these solutions and their linear stability are also discussed.
Article
Physics, Multidisciplinary
Shiwei Shen, Tian Qin, Jingjing Gao, Chenhaoping Wen, Jinghui Wang, Wei Wang, Jun Li, Xuan Luo, Wenjian Lu, Yuping Sun, Shichao Yan
Summary: The realization of Kondo lattice in superconducting van der Waals materials allows for the tuning of its behavior by electrical gating or intercalation and contributes to understanding heavy fermion superconductivity. This study focuses on a superconducting compound (4Hb-TaS2) with alternating stacking of 1T-TaS2 and 1H-TaS2 layers, using low-temperature vector-magnetic-field scanning tunneling microscopy and spectroscopy. Quasi-two-dimensional superconductivity is observed in the 1H-TaS2 layer with anisotropic response to magnetic fields. The Kondo resonance peak resulting from the Kondo screening of unpaired electrons in the Star-of-David clusters is detected in the 1T-TaS2 layer. The intensity of the Kondo resonance peak is found to be sensitive to its relative position with the Fermi level and can be enhanced by evaporating Pb atoms onto the 1T-TaS2 surface. These findings contribute to a better understanding of the electronic properties of 4Hb-TaS2 and offer a pathway to creating tunable Kondo lattice in superconducting van der Waals materials.
CHINESE PHYSICS LETTERS
(2022)
Article
Physics, Multidisciplinary
Francesco Petocchi, Christopher W. Nicholson, Bjoern Salzmann, Diego Pasquier, Oleg Yazyev, Claude Monney, Philipp Werner
Summary: We address the problem of the ground state of 1T-TaS2 by studying the correlated electronic structure of stacked bilayers. The surface termination determines whether the uncorrelated system is band insulating or exhibits a metallic surface state. A Mott gap opens in the surface state but is smaller than the gap originating from the bilayer structure. Our results are consistent with recent experimental measurements and clarify the interplay between Mott insulating and band insulating behavior in this system.
PHYSICAL REVIEW LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Li Cheng, Xuanyu Long, Xiaobin Chen, Xiaolong Zou, Zheng Liu
Summary: The study shows that a flat band in 1T-TaS2 can be understood by adjusting the t(2g) basis, and the rehybridization of three orbitals by the CDW order leads to the formation of the flat band.
Article
Multidisciplinary Sciences
Sangjun Lee, Edwin W. Huang, Thomas A. Johnson, Xuefei Guo, Ali A. Husain, Matteo Mitrano, Kannan Lu, Alexander Zakrzewski, Gilberto A. de la Pena, Yingying Peng, Hai Huang, Sang-Jun Lee, Hoyoung Jang, Jun-Sik Lee, Young Il Joe, William B. Doriese, Paul Szypryt, Daniel S. Swetz, Songxue Chi, Adam A. Aczel, Gregory J. MacDougall, Steven A. Kivelson, Eduardo Fradkin, Peter Abbamonte
Summary: The behavior of charge density waves (CDWs) in different families of copper-oxide superconductors has been studied. This research found that the CDW amplitude is temperature independent and develops well above experimentally accessible temperatures. The CDW wavevector shows a nonmonotonic temperature dependence, exhibiting different behaviors at low temperatures and near the spin ordering temperature. The study suggests a common mechanism for CDW order in all families of cuprates.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Materials Science, Multidisciplinary
Jingwei Dong, Weiyan Qi, Dongbin Shin, Laurent Cario, Zhesheng Chen, Romain Grasset, Davide Boschetto, Mateusz Weis, Pierrick Lample, Ernest Pastor, Tobias Ritschel, Marino Marsi, Amina Taleb, Noejung Park, Angel Rubio, Evangelos Papalazarou, Luca Perfetti
Summary: This study compares the bulk and surface properties of the transition metal dichalcogenide 1T-TaS2. It is found that when heating the sample, the surface exhibits an intermediate insulating phase while the bulk remains metallic. The amplitude mode at the surface is always stiffer and shows variable coupling to the Mott-Peierls band in different phases.
Article
Materials Science, Multidisciplinary
Lukas Schwarz, Rafael Haenel, Dirk Manske
Summary: This paper introduces the use of THG experiments on superconductors to study collective excitations like the Higgs mode, and additionally analyzes the phase of the THG signal for the first time, highlighting the importance of phase information in interpreting experimental results.
Article
Multidisciplinary Sciences
Huimin Zhang, Basu Dev Oli, Qiang Zou, Xu Guo, Zhengfei Wang, Lian Li
Summary: In FeSn, we observe the symemtry-breaking and tunable electronic orders in the Kagome lattice by applying a magnetic field, providing a new avenue for studying the unique quantum states in Kagome lattice.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Shiwei Shen, Chenhaoping Wen, Pengfei Kong, Jingjing Gao, Jianguo Si, Xuan Luo, Wenjian Lu, Yuping Sun, Gang Chen, Shichao Yan
Summary: Researchers demonstrate a transition from an insulating gap to a tunable Kondo resonance in 1T-TaS2 by Pb intercalation, providing a pathway for creating and tuning many-body electronic states in layered narrow-electronic-band materials.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Ziying Wang, Zishen Wang, Yuan Ping Feng, Kian Ping Loh
Summary: Chirality plays a crucial role in spontaneous symmetry breaking and has a profound impact on the topology, charge, and spin orders of materials. This study reports the observation of predominantly chiral charge density wave (CDW) phase in two-dimensional H-phase TaS2 synthesized by molecular-beam epitaxy (MBE). Scanning tunneling microscopy (STM) imaging and first-principles calculations reveal the chirality origin in the CDW phase. This work provides new insights into the physical origin of chiral charge-ordered states and sheds light on a general ordering rule in chiral CDWs.
Article
Physics, Multidisciplinary
Wei Ruan, Yi Chen, Shujie Tang, Jinwoong Hwang, Hsin-Zon Tsai, Ryan L. Lee, Meng Wu, Hyejin Ryu, Salman Kahn, Franklin Liou, Caihong Jia, Andrew Aikawa, Choongyu Hwang, Feng Wang, Yongseong Choi, Steven G. Louie, Patrick A. Lee, Zhi-Xun Shen, Sung-Kwan Mo, Michael F. Crommie
Summary: Research has shown that some quantum spin liquids may have an effective Fermi surface of fractionalized spinon excitations. The material 1T-TaSe2 is believed to have charge density modulations caused by an unstable spinon Fermi surface. Through scanning tunnelling spectroscopy, researchers have imaged density waves consistent with the predictions of spinon density modulation in single-layer 1T-TaSe2. Additionally, spectroscopic imaging of isolated single-layer 1T-TaSe2 has revealed long-wavelength super-modulations consistent with the behavior of itinerant spinons, allowing the experimental measurement of the spinon Fermi wavevector.
Article
Chemistry, Multidisciplinary
Hossain Mohammad Ikram, Ara Ferdous, Shahed Syed Mohammad Fakruddin, Zhipeng Wang, Tadahiro Komeda
Summary: We report the finding of a 1T phase island of NbSe2 on a cleaved surface and its magnetic properties. The magnetic moment placed in the superconducting state generates the Yu-Shiba-Rusinov (YSR) state with specific position and anisotropic decay behavior. The enhancement of the YSR peak is closely related to the local curvature of the film.
Article
Physics, Atomic, Molecular & Chemical
A. Alfonsov, B. Buechner, V. Kataev
Summary: The study proposes the use of a cantilever-based setup to overcome challenges posed by small sample sizes, enabling detection of static magnetic response and ESR signal in novel magnetic materials samples.
APPLIED MAGNETIC RESONANCE
(2022)
Article
Physics, Multidisciplinary
Rui Lou, Alexander Fedorov, Qiangwei Yin, Andrii Kuibarov, Zhijun Tu, Chunsheng Gong, Eike F. Schwier, Bernd Buechner, Hechang Lei, Sergey Borisenko
Summary: The entanglement of charge density wave (CDW), superconductivity, and topologically nontrivial electronic structure has been discovered in the kagome metal AV3Sb5 (A = K, Rb, Cs) family recently. Using high-resolution angle-resolved photoemission spectroscopy, the electronic properties of CDW and superconductivity in CsV3Sb5 are studied. The spectra around K over line exhibit a peak-dip-hump structure associated with two separate branches of dispersion, indicating the isotropic CDW gap opening below EF. The presence of a superconducting gap on both the electron band around Gamma over line and the flat band around K suggests multiband superconductivity. Our results shed light on the controversial origin of the CDW and provide insights into the relationship between CDW and superconductivity.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Seung-Ho Baek, Yeahan Sur, Kee Hoon Kim, Matthias Vojta, Bernd Buechner
Summary: Single crystals of pristine and 6% Pd-intercalated 2H-TaSe2 were studied using Se-77 nuclear magnetic resonance. The Se-77 spectrum showed line narrowing upon Pd intercalation, indicating the presence of correlated local lattice distortions above the charge density wave (CDW) transition temperature. The Knight shift data suggested a partial Fermi surface gap opening in the incommensurate CDW transition. The spin dynamics study revealed a pseudogap behavior dominating the low-energy spin excitations, which gets stronger along with superconductivity in the Pd-6% sample.
NEW JOURNAL OF PHYSICS
(2022)
Article
Multidisciplinary Sciences
Shu-Jen Wang, Michel Panhans, Ilia Lashkov, Hans Kleemann, Federico Caglieris, David Becker-Koch, Joern Vahland, Erjuan Guo, Shiyu Huang, Yulia Krupskaya, Yana Vaynzof, Bernd Buechner, Frank Ortmann, Karl Leo
Summary: The charge and thermoelectric transport in modulation-doped large-area rubrene thin-film crystals with different crystal phases were investigated. The results showed that modulation doping, together with high-mobility crystalline organic semiconductor films, is a previously unexplored strategy for achieving high-performance organic thermoelectrics. Theoretical studies provided insight into the energy landscape of the heterostructures and its influence on qualitative trends of the Seebeck coefficient.
Article
Multidisciplinary Sciences
Sergey Borisenko, Alexander Fedorov, Andrii Kuibarov, Marco Bianchi, Volodymyr Bezguba, Paulina Majchrzak, Philip Hofmann, Peter Baumgaertel, Vladimir Voroshnin, Yevhen Kushnirenko, Jaime Sanchez-Barriga, Andrei Varykhalov, Ruslan Ovsyannikov, Igor Morozov, Saicharan Aswartham, Oleh Feia, Luminita Harnagea, Sabine Wurmehl, Alexander Kordyuk, Alexander Yaresko, Helmuth Berger, Bernd Buechner
Summary: Fermi surfaces are crucial for understanding the properties of crystalline metals and semiconductors. A new angle-resolved photoemission spectroscopy technique is presented that allows for fast and high-resolution mapping of the Fermi surface.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Abdul-Vakhab Tcakaev, Bastian Rubrecht, Jorge. Facio, Volodymyr. B. Zabolotnyy, Laura. T. Corredor, Laura. C. Folkers, Ekaterina Kochetkova, Thiago R. F. Peixoto, Philipp Kagerer, Simon Heinze, Hendrik Bentmann, Robert. J. Green, Pierluigi Gargiani, Manuel Valvidares, Eugen Weschke, Maurits. W. Haverkort, Friedrich Reinert, Jeroen van den Brink, Bernd Buechner, Anja U. B. Wolter, Anna Isaeva, Vladimir Hinkov
Summary: The recent discovery of the quantum anomalous Hall effect (QAHE) in MnBi2Te4 and MnBi4Te7 indicates the potential of the (MnBi2Te4)(Bi2Te3)(n) family for further improvements in QAHE. The ferromagnetic (FM) ordered MnBi2Te4 septuple layers (SLs) in this family contribute to its promising nature. However, achieving QAHE in MnBi2Te4 and MnBi4Te7 is complicated due to the substantial antiferromagnetic (AFM) coupling between the SLs. By interlacing the SLs with an increasing number of Bi2Te3 quintuple layers (QLs), an FM state advantageous for QAHE can be stabilized. The mechanisms driving the FM state and the number of necessary QLs are not yet understood, and the surface magnetism remains unclear. This study demonstrates robust FM properties in MnBi6Te10 (n = 2) and establishes that its origin lies in the Mn/Bi intermixing phenomenon, thus consolidating its potential for QAHE at elevated temperatures.
Article
Physics, Condensed Matter
A. S. Cameron, Y. Tymoshenko, P. Y. Portnichenko, A. S. Sukhanov, M. Ciomaga Hatnean, D. McK Paul, G. Balakrishnan, R. Cubitt, D. S. Inosov
Summary: In previous studies, the noncentrosymmetric superconductor Ru7B3 has shown unusual behavior in its vortex lattice, with vortices dissociating from the crystal lattice and exhibiting a complex field-history dependence. In this study, the vortex lattice form factor of Ru7B3 was investigated to check for deviations from established models. The results suggest that the anisotropic London model is a good fit, indicating minimal alterations to the vortex structure due to broken inversion symmetry. Penetration depth and coherence length were also extracted from the data.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Physics, Multidisciplinary
P. Kagerer, C. I. Fornari, S. Buchberger, T. Tschirner, L. Veyrat, M. Kamp, A. V. Tcakaev, V. Zabolotnyy, S. L. Morelhao, B. Geldiyev, S. Mueller, A. Fedorov, E. Rienks, P. Gargiani, M. Valvidares, L. C. Folkers, A. Isaeva, B. Buechner, V. Hinkov, R. Claessen, H. Bentmann, F. Reinert
Summary: Inducing a magnetically-induced gap in the Dirac point of a three-dimensional topological insulator can result in dissipationless charge and spin currents. In this study, the authors use a ferromagnetic extension technique to create a robust 2D ferromagnetic material on the surface of a 3D topological insulator. The results demonstrate the opening of a sizable magnetic gap in the 2D ferromagnetic phase, while the surface remains gapless in the paramagnetic phase.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Materials Science, Multidisciplinary
Anton A. Kulbakov, Elaheh Sadrollahi, Florian Rasch, Maxim Avdeev, Sebastian Gass, Laura Teresa Corredor Bohorquez, Anja U. B. Wolter, Manuel Feig, Roman Gumeniuk, Hagen Poddig, Markus Stoetzer, F. Jochen Litterst, Ines Puente-Orench, Andrew Wildes, Eugen Weschke, Jochen Geck, Dmytro S. Inosov, Darren C. Peets
Summary: In frustrated magnetic systems, the competition among interactions can introduce high degeneracy, leading to a lack of unique ground state. Antlerite mineral exhibits various magnetically ordered phases depending on the balance among interactions, making it a promising platform for exploring exotic magnetic order.
Article
Materials Science, Multidisciplinary
Stanislav M. Avdoshenko, Anton A. Kulbakov, Ellen Haeussler, Philipp Schlender, Thomas Doert, Jacques Ollivier, Dmytro S. Inosov
Summary: Layered rare-earth delafossites ARX(2) are potential hosts for a quantum spin-liquid ground state. Some systems show no long-range order down to the lowest temperatures, while others exhibit antiferromagnetic order at subkelvin temperatures.
Article
Materials Science, Multidisciplinary
A. S. Sukhanov, V. Ukleev, P. Vir, P. Gargiani, M. Valvidares, J. S. White, C. Felser, D. S. Inosov
Summary: Multiple intriguing phenomena have been discovered in tetragonal Heusler compounds with D-2d symmetry, which leads to a unique interplay between Dzyaloshinskii-Moriya (DM) and magnetic dipolar interactions. By conducting experiments on high-quality single crystals of Mn1.4PtSn at low temperatures using resonant small-angle soft x-ray scattering, researchers have provided evidence of how the underlying D-2d symmetry of the DM interaction is reflected in the magnetic texture of this material. The study reveals the existence of a novel and complex metastable phase that forms at low temperature in zero fields upon in-plane field training, which possibly has a mixed character of both the Neel-type cycloid and the Bloch-type helix.
Article
Materials Science, Multidisciplinary
A. Kuibarov, A. Fedorov, V. Bezguba, H. Berger, A. Yaresko, V. Voroshnin, A. Kordyuk, P. Baumgaertel, B. Buechner, S. Borisenko
Summary: Using angle-resolved photoemission spectroscopy, this study revisits the electronic structure of BiTeI and proposes an alternative description based on the experimentally determined crystal structure. The results show that BiTeI is a topological 3D Dirac semimetal with only two, well isolated Dirac points in its band structure.
Article
Materials Science, Multidisciplinary
A. S. Sukhanov, Y. V. Tymoshenko, A. A. Kulbakov, A. S. Cameron, V. Kocsis, H. C. Walker, A. Ivanov, J. T. Park, V. Pomjakushin, S. E. Nikitin, I. V. Morozov, I. O. Chernyavskii, S. Aswartham, A. U. B. Wolter, A. Yaresko, B. Buechner, D. S. Inosov
Summary: FeP is a special material with complex noncollinear spin order. By measuring the spin-excitation spectra, we found that the magnons in FeP have strong anisotropic dispersions. The dominant antiferromagnetic interactions between rigid ferromagnetic spin chains drive the magnetic frustration in FeP.
Article
Materials Science, Multidisciplinary
Vilmos Kocsis, David A. S. Kaib, Kira Riedl, Sebastian Gass, Paula Lampen-Kelley, David G. Mandrus, Stephen E. Nagler, Nicolas Perez, Kornelius Nielsch, Bernd Buechner, Anja U. B. Wolter, Roser Valenti
Summary: In this combined theoretical and experimental research, the anisotropic magnetic and magnetoelastic properties of the Kitaev material alpha-RuCl3 were investigated. Unusually large magnetostriction anisotropy and non-symmetric magnetic anisotropy were observed, and their origins were explained based on the relative orientation of the magnetization with respect to the crystal structure.
Article
Materials Science, Multidisciplinary
F. Bougamha, S. Selter, Y. Shemerliuk, S. Aswartham, A. Benali, B. Buechner, H-J Grafe, A. P. Dioguardi
Summary: We report the anomalous breakdown in the scaling of the microscopic magnetic susceptibility with the bulk magnetic susceptibility in Mn2P2S6. NMR spectra provide evidence for domain rotation and spin-flop transition in the magnetic state. A spin-flop-induced splitting of the NMR spectra is observed in Ni2P2S6.
