Article
Multidisciplinary Sciences
Faranak Bahrami, Xiaodong Hu, Yonghua Du, Oleg Lebedev, Chennan Wang, Hubertus Luetkens, Gilberto Fabbris, Michael J. Graf, Daniel Haskel, Ying Ran, Fazel Tafti
Summary: Recent observations of novel spin-orbit coupled states have generated interest in 4d/5d transition metal systems. In this study, we manipulate the competition between spin-orbit interaction and crystal field to restructure the spin-orbital wave functions and discover a previously unobserved state that drives Ising interactions.
Article
Materials Science, Multidisciplinary
T. Harada
Summary: Metallic delafossites are layered materials with high electrical conductivity and surface polarity, enabling the fabrication of heterostructures and quantum devices. The surface polarity of metallic delafossites plays a significant role in influencing electron movement and inducing spin-dependent surface states, making them promising for various device functionalities. However, the challenge lies in achieving high-quality thin films for practical applications.
MATERIALS TODAY ADVANCES
(2021)
Article
Materials Science, Multidisciplinary
Faranak Bahrami, Eric M. Kenney, Chennan Wang, Adam Berlie, Oleg Lebedev, Michael J. Graf, Fazel Tafti
Summary: The comparative study of two samples of Ag3LiIr2O6 in clean and disordered limits reveals the potential presence of an approximate spin liquid state in the disordered limit, while long-range antiferromagnetic order is confirmed in the clean limit. Structural disorder plays a significant role in the behavior of intercalated Kitaev magnets.
Article
Materials Science, Multidisciplinary
Mikael Fremling, Lars Fritz
Summary: In this work, the researchers investigate the possibility of using the Kitaev honeycomb model to realize the physics of the Sachdev-Ye-Kitaev (SYK) model. By straining the system and inducing effective interactions between Majorana modes, a bipartite SYK model with similar properties as the standard SYK model is obtained. The conditions for observing the standard SYK model in this setup are also hypothesized.
Article
Materials Science, Multidisciplinary
Tommy McKinnon, Bret Heinrich, Erol Girt
Summary: The bilinear interlayer magnetic coupling J(1) between two Co layers separated by a Ru spacer layer was measured over a wide range of spacer layer thicknesses and temperatures. Multiple critical spanning vectors contribute to J(1), each with different oscillation periods relative to the spacer layer thickness. The findings suggest that there is no exponential superexchange-like contribution to coupling in the samples, and the interface-reflection model adequately describes the bilinear interlayer exchange coupling across different spacer layer thicknesses and temperatures.
Article
Physics, Applied
Yi Cao, Xiaomin Zhang, Xian-Peng Zhang, Faguang Yan, Ziao Wang, Wenkai Zhu, Hao Tan, Vitaly N. Golovach, Houzhi Zheng, Kaiyou Wang
Summary: This study shows that the magnetic properties of vdW Fe3GeTe2 can be tuned by interlayer exchange coupling (IEC). Ferromagnetic coupling enhances the Curie temperature and maintains perpendicular magnetic anisotropy (PMA), while antiferromagnetic coupling weakens the PMA.
PHYSICAL REVIEW APPLIED
(2022)
Article
Chemistry, Multidisciplinary
Zidong Li, Xiaobo Lu, Darwin F. Cordovilla Leon, Zhengyang Lyu, Hongchao Xie, Jize Hou, Yanzhao Lu, Xiaoyu Guo, Austin Kaczmarek, Takashi Taniguchi, Kenji Watanabe, Liuyan Zhao, Li Yang, Parag B. Deotare
Summary: This study experimentally quantifies the diffusion barrier experienced by interlayer excitons in MoSe2/WSe2 heterostructures with different twist angles and attributes it to the deep periodic potentials arising from the moire superlattice. The observations are supported by theoretical calculations, Monte Carlo simulations, and a three-level model representing the exciton dynamics at various temperatures.
Article
Physics, Multidisciplinary
Xiaosong Deng, Kui Gong, Yin Wang, Zebin Liu, Kaili Jiang, Ning Kang, Zhiyong Zhang
Summary: In this study, a double split-gate structure was constructed to explore the Aharonov-Bohm interference effect in individual single-wall carbon nanotube p-n junction devices. The AB modulation of conductance was achieved with coaxial magnetic fields as low as 3 T, where the flux through the tube is much smaller than the flux quantum. Moreover, electric-field control of the nonmonotonic magnetoconductance was demonstrated through a gate-tunable built-in electric field, which can be quantitatively understood in combination with the AB phase effect and Landau-Zener tunneling in a CNT p-n junction.
PHYSICAL REVIEW LETTERS
(2023)
Article
Nanoscience & Nanotechnology
Wei Cao, Oded Hod, Michael Urbakh
Summary: We have discovered that the complex ferroelectric response of layered materials towards interlayer sliding is determined by the interlayer lattice registry. The entire sliding polarization landscape of two-dimensional layered material interfaces can be described using the polarization registry index (PRI), a simple geometric measure that quantifies the degree of interlayer commensurability. This tool not only aids in understanding the fundamental origin of 2D ferroelectricity, but also allows for efficient characterization and rationalization of existing experimental and computational evidence, as well as prediction of emergent controllable polarization in new noncentrosymmetric layered systems.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Physics, Multidisciplinary
D. A. Bandurin, A. Principi, I. Y. Phinney, T. Taniguchi, K. Watanabe, P. Jarillo-Herrero
Summary: This study demonstrates that small-angle twisted bilayer graphene provides a highly tunable system for exploring interactions-limited electron conduction. Through the development of e-h drag theory, we reveal strong mutual friction between electrons and holes and clarify the conduction mechanisms in charge-neutral SATBG.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Applied
Meixin Cheng, Shazhou Zhong, Nicolas Rivas, Tina Dekker, Ariel Alcides Petruk, Patrick Gicala, Kostyantyn Pichugin, Fangchu Chen, Xuan Luo, Yuping Sun, Adam W. Tsen, German Sciaini
Summary: In this study, time-resolved broadband transient reflectivity (tr-bb-TR) measurements were used to investigate the photoinduced electronic changes and dynamics of interlayer shear phonon in T-d-MoTe2 single crystal under different incident pump fluences. The results show a gradual evolution of both the photoinduced electronic changes and interlayer shear phonon Fourier spectra as a function of pump fluence, ruling out the threshold-like change associated with the ultrafast photoinduced phase transition. Additionally, a large redshift of the interlayer shear phonon Fourier spectral features suggests significant renormalization effects on the dielectrically susceptible interband transitions.
APPLIED PHYSICS LETTERS
(2022)
Article
Chemistry, Physical
Jia-Pei Deng, Hong-Juan Li, Xu-Fei Ma, Xiao-Yi Liu, Yu Cui, Xin-Jun Ma, Zhi-Qing Li, Zi-Wu Wang
Summary: In this study, we investigated the self-trapping mechanism of interlayer excitons in van der Waals heterostructures and found that the interplay between the electron and hole effective masses can induce self-trapped states with increasing or decreasing binding energies for excitons. Our results shed light on the modulation of interlayer excitons and provide new insights into their control.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Honglian Chen, Songjun Hou, Qingqing Wu, Feng Jiang, Ping Zhou, Long Zhang, Yang Jiao, Bo Song, Qing-Hu Guo, Xiao-Yang Chen, Wenjing Hong, Colin J. Lambert, J. Fraser Stoddart
Summary: Single-molecule electronics focuses on studying the flow of electricity through devices made of single molecules, with the control of current flow being influenced by quantum interference. Research has shown that in tetracationic cyclophane circuits, electron transport is mediated by quantum interference between two lowest unoccupied molecular orbitals, resulting in either constructive or destructive interference and impacting overall conductivity. This design allows for the construction of single-molecule conductors and insulators based on a single cyclophane platform.
Article
Physics, Multidisciplinary
Jean Cappello, Olivia Du Roure, Francois Gallaire, Camille Duprat, Anke Lindner
Summary: This study explores the dynamics of a flexible fiber transported by a viscous flow in a Hele-Shaw cell of comparable height to the fiber. It is found that long fibers aligned with the flow experience buckling instability, with competition between viscous and elastic forces resulting in the fiber deforming into a wavy shape convolved by a Bell-shaped envelope. The spatiotemporal evolution of the deformation reveals a linear and absolute instability described by the Ginzburg-Landau equation.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Jianting Ji, Mengjie Sun, Yanzhen Cai, Yimeng Wang, Yingqi Sun, Wei Ren, Zheng Zhang, Feng Jin, Qingming Zhang
Summary: Rare-earth chalcohalides REChX are identified as a family of Kitaev spin liquid (KSL) candidates, with high symmetry structures and strong spin-orbit coupling of 4f electrons providing the required anisotropic spin interactions for the Kitaev model.
CHINESE PHYSICS LETTERS
(2021)
Article
Multidisciplinary Sciences
A. Inbar, J. Birkbeck, J. Xiao, T. Taniguchi, K. Watanabe, B. Yan, Y. Oreg, Ady Stern, E. Berg, S. Ilani
Summary: The invention of the quantum twisting microscope (QTM) allows for direct observation of key quantum properties of electronic systems. By creating pristine two-dimensional junctions and using a unique van der Waals tip, the QTM enables local interference experiments at its tip, providing a multitude of interfering paths for electrons to tunnel into a sample. Through various experiments, the QTM demonstrates room-temperature quantum coherence, studies the evolution of twist angles in twisted bilayer graphene, images the energy bands of monolayer and twisted bilayer graphene, and visualizes the flattening of the low-energy band of twisted bilayer graphene under local pressure. The QTM opens up new possibilities for studying quantum materials.
Article
Physics, Multidisciplinary
Belen E. Zuniga-Cespedes, Kaustuv Manna, Hilary M. L. Noad, Po-Ya Yang, Michael Nicklas, Claudia Felser, Andrew P. Mackenzie, Clifford W. Hicks
Summary: By applying a combination of uniaxial stress and magnetic field, we have observed a significant anomalous Hall effect in a bulk sample of a cubic member of the Mn3X family for the first time. The observed effect remains unchanged when the stress is removed, indicating that it is not induced by stress-induced ferromagnetic moments.
NEW JOURNAL OF PHYSICS
(2023)
Article
Physics, Multidisciplinary
Edgar Abarca Morales, Gesa-R. Siemann, Andela Zivanovic, Philip A. E. Murgatroyd, Igor Markovic, Brendan Edwards, Chris A. Hooley, Dmitry A. Sokolov, Naoki Kikugawa, Cephise Cacho, Matthew D. Watson, Timur K. Kim, Clifford W. Hicks, Andrew P. Mackenzie, Phil D. C. King
Summary: We present the evolution of the electronic structure at the surface of Sr2RuO4 under large in-plane uniaxial compression, resulting in anisotropic B1g strains. Using angle-resolved photoemission, we observe a sequence of Lifshitz transitions that reshape the electronic structure and van Hove singularities on the surface. Our study reveals the nature of structural distortions at oxide surfaces and the possibility of controlling the density of state singularities for the realization of collective states at the Sr2RuO4 surface.
PHYSICAL REVIEW LETTERS
(2023)
Article
Instruments & Instrumentation
F. Sun, S. Mishra, P. H. McGuinness, Z. H. Filipiak, I. Markovic, D. A. Sokolov, N. Kikugawa, J. W. Orenstein, S. A. Hartnoll, A. P. Mackenzie, V. Sunko
Summary: We propose an optical method for directly measuring the position-dependent thermal diffusivity of reflective single crystal samples in condensed matter physics research. By using two laser beams, one to modulate the sample temperature and the other to probe sample reflectivity, we obtain the thermal diffusivity by analyzing the phase delay between the two signals. This technique can provide spatially resolved measurements and enhanced spatial resolution to a micron scale. We demonstrated the effectiveness of this method on two stoichiometric bilayer ruthenates and Ti-doped Ca3Ru2O7, revealing temperature-dependent diffusivity and inhomogeneity.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2023)
Article
Multidisciplinary Sciences
Carsten Putzke, Chunyu Guo, Vincent Plisson, Martin Kroner, Thibault Chervy, Matteo Simoni, Pim Wevers, Maja D. Bachmann, John R. Cooper, Antony Carrington, Naoki Kikugawa, Jennifer Fowlie, Stefano Gariglio, Andrew P. Mackenzie, Kenneth S. Burch, Atac Imamoglu, Philip J. W. Moll
Summary: The quest to improve transparent conductors lies in balancing high electrical conductivity and optical transparency. This study demonstrates that this can be achieved by separating the directionality of optical and electrical conductivity through the use of highly anisotropic crystalline conductors.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Kyuil Cho, Marcin Konczykowski, Makariy A. Tanatar, Igor I. Mazin, Yong Liu, Thomas A. Lograsso, Ruslan Prozorov
Summary: Low-temperature variable-energy electron irradiation induced non-magnetic disorder in a hole-doped iron-based superconductor Ba1-xKxFe2As2, x = 0.80. The resistivity of the sample increased linearly with irradiation fluence, indicating the creation of uncorrelated dilute point-like disorder. The predominant creation of defects in the iron sublattice was confirmed by comparing with calculated partial cross-sections. Simultaneously, the superconducting transition temperature was monotonically suppressed due to the total scattering rate, supporting the assumption of the dominant role of the iron sub-lattice in iron-based superconductors.
Article
Physics, Multidisciplinary
K. Ishihara, M. Kobayashi, K. Imamura, M. Konczykowski, H. Sakai, P. Opletal, Y. Tokiwa, Y. Haga, K. Hashimoto, T. Shibauchi
Summary: The exotic superconducting properties of the paramagnetic spin-triplet superconductor candidate UTe2, such as extremely high upper critical field and possible chiral superconducting states, have attracted significant attention. This study focuses on the thermodynamic critical field Hc, the lower critical field Hc1, and the upper critical field Hc2 at low fields of ultraclean single crystals of UTe2, providing crucial insight into its intrinsic superconducting properties. Anomalous enhancement of Hc1 values with magnetic field along the b and c axes, showing unusual low-temperature upturns, is attributed to the effect of strong Ising-like ferromagnetic fluctuations on the vortex line energy.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Materials Science, Multidisciplinary
V. Sunko, Y. Sun, M. Vranas, C. C. Homes, C. Lee, E. Donoway, Z. -c. Wang, S. Balguri, M. B. Mahendru, A. Ruiz, B. Gunn, R. Basak, S. Blanco-Casnosa, E. Schierle, E. Weschke, F. Tafti, A. Frano, J. Orenstein
Summary: EuCd2P2 exhibits unconventional transport with a giant peak in resistivity at 18 K, which is above the Neel temperature. Using various sensitive probes of magnetism, it has been found that ferromagnetic order starts above TN in the temperature range of the resistivity peak and is promoted by the coupling of localized spins and itinerant carriers. The carrier localization is confirmed by optical conductivity measurements.
Article
Materials Science, Multidisciplinary
Elina Zhakina, Philippa H. McGuinness, Markus Koenig, Romain Grasset, Maja D. Bachmann, Seunghyun Khim, Carsten Putzke, Philip J. W. Moll, Marcin Konczykowski, Andrew P. Mackenzie
Summary: High-energy electron irradiation is used to study the effects on PtCoO2, and it is found that this technique can transition from nonlocal to local transport behavior, thus determining the nature and extent of unconventional transport regimes.
Article
Materials Science, Multidisciplinary
Fabian Jerzembeck, Alexander Steppke, Andrej Pustogow, Yongkang Luo, Aaron Chronister, Dmitry A. Sokolov, Naoki Kikugawa, You-Sheng Li, Michael Nicklas, Stuart E. Brown, Andrew P. Mackenzie, Clifford W. Hicks
Summary: In-plane uniaxial pressure can strongly tune the superconducting state of Sr2RuO4 by approaching a Lifshitz transition and associated Van Hove singularity (VHS) in the density of states. The in-plane upper critical field is mostly linear in Tc, while the out-of-plane upper critical field varies with a higher power in Tc and peaks strongly at the VHS. The change in magnitude and form of Hc2||c occur very close to the Van Hove strain, pointing to a strong enhancement of both the density of states and the gap magnitude at the Lifshitz transition.
Article
Materials Science, Multidisciplinary
J. Sitnicka, M. Konczykowski, K. Sobczak, P. Skupinski, K. Grasza, Z. Adamus, A. Reszka, A. Wolos
Summary: This study focuses on the magnetic coupling mechanisms in magnetically doped topological insulators (TIs) and investigates the role of bulk carriers and the effect of Fermi level tuning on magnetism and magnetotransport. The results show that the quantum anomalous Hall effect (AHE) can be effectively managed, maximized, or turned off by adjusting the Fermi level position.
