Article
Chemistry, Physical
Jeong Min Park, Yuan Cao, Li-Qiao Xia, Shuwen Sun, Kenji Watanabe, Takashi Taniguchi, Pablo Jarillo-Herrero
Summary: Superconductivity has been observed in magic-angle twisted four-layer and five-layer graphene systems, expanding the family of moire superconductors. The distinction between the twisted bilayer graphene and other members of the family is related to the movement of electrons between layers in a magnetic field. This discovery provides new insights for the design of superconducting materials platforms.
Article
Physics, Multidisciplinary
A. Stupakiewicz, C. S. Davies, K. Szerenos, D. Afanasiev, K. S. Rabinovich, A. V. Boris, A. Caviglia, A. V. Kimel, A. Kirilyuk
Summary: Researchers have achieved switching of magnetization in magnetic garnet films by ultrafast resonant excitation of longitudinal optical phonon modes, revealing the magneto-elastic mechanism of the switching. In contrast, excitation of strongly absorbing transverse phonon modes results in a thermal demagnetization effect only.
Article
Chemistry, Physical
M. Slezak, P. Drozdz, K. Matlak, A. Koziol-Rachwal, A. A. Sasikala Devi, M. Alatalo, T. Slezak
Summary: Gas adsorption on the surface of (Fe/Co)(N) superlattices drives the rotation of magnetization angle in Fe(110) ferromagnet. The sensitivity of spin orientation to adsorption can be controlled by terminating the surface with Co or Fe. The purely surface-limited adsorption process alters the magnetic anisotropy of the entire superlattice, making it an artificial surface.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Astronomy & Astrophysics
Jae Hyeok Chang, Maria Olalla Olea-Romacho, Erwin H. Tanin
Summary: Finite temperature effects in the early universe tend to restore the electroweak symmetry in the Standard Model, but new fields coupled to the Higgs field may reverse this tendency, leading to electroweak symmetry nonrestoration. Previous studies assumed that this reversal is due to thermal fluctuations of new fields, but we found that it can be minimally realized if the fields coupled to the Higgs field develop a stable condensate.
Article
Materials Science, Multidisciplinary
Zhijun Jiang, Bin Xu, Sergey Prosandeev, Yousra Nahas, Sergei Prokhorenko, Jorge Iniguez, L. Bellaiche
Summary: An atomistic effective Hamiltonian is applied to calculate electrocaloric effects in rare-earth-substituted BiFeO3 multiferroics, followed by the development of a phenomenological model to interpret these calculations. The model suggests that the electrocaloric coefficient is determined by two terms involving electric quantities and the antiferromagnetic order parameter.
Article
Materials Science, Multidisciplinary
Ningbo Fan, Jorge Iniguez, L. Bellaiche, Bin Xu
Summary: Based on first-principles calculations, this study investigates the electrocaloric effect in Nd-substituted BiFeO3 perovskite solid solutions, revealing a new mechanism for achieving anomalous electrocaloric effects by explicitly considering octahedral tiltings.
Article
Physics, Condensed Matter
A. B. Felix de Souza, L. Spreafico, D. Faria, A. Latge
Summary: The synthesis of new materials has stimulated interest in exploring properties of systems with complex lattices. Two-dimensional super-honeycomb lattices in metallic organic frameworks exhibit localized electronic responses as flat bands with topological isolating behavior. This study analyzes the electron-electron correlation effects on the topological phases of 2D and quasi-1D graphene-Kagome lattices using Hubbard mean-field approximation. The results provide insights for developing nanostructured devices with applications in spintronics and transport responses.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Review
Physics, Applied
Pierre A. Pantaleon, Alejandro Jimeno-Pozo, Hector Sainz-Cruz, Phong Vo Tien, Tommaso Cea, Francisco Guinea
Summary: This Perspective article summarizes the study of superconductivity and correlated phases in non-twisted graphene bilayers and trilayers. The authors provide an overview of the recent experimental findings and analyze the theoretical models that aim to explain them. Superconductivity and cascades of correlated phases have been discovered in Bernal bilayer and rhombohedral trilayer graphene.
NATURE REVIEWS PHYSICS
(2023)
Article
Multidisciplinary Sciences
Alexis Coissard, David Wander, Hadrien Vignaud, Adolfo G. Grushin, Cecile Repellin, Kenji Watanabe, Takashi Taniguchi, Frederic Gay, Clemens B. Winkelmann, Herve Courtois, Hermann Sellier, Benjamin Sacepe
Summary: In this study, three distinct broken-symmetry phases in graphene were directly imaged using scanning tunnelling spectroscopy. It was found that graphene exhibits different lattice-scale orders under different conditions, deviating from current theoretical predictions. These findings are important for uncovering correlated phases of matter in other quantum materials.
Article
Chemistry, Inorganic & Nuclear
Jan. A. Zienkiewicz, Karolina Kaldunska, Katarzyna Fedoruk, Antonio J. Barros dos Santos, Mariusz Stefanski, Waldeci Paraguassu, Tadeusz M. Muziol, Maciej Ptak
Summary: The synthesis and investigation of a novel one-dimensional organic-inorganic hybrid perovskite with unique physicochemical properties are reported. The crystal structure and phase transitions of the material are studied, and its optical properties are characterized, suggesting potential applications.
INORGANIC CHEMISTRY
(2022)
Article
Chemistry, Inorganic & Nuclear
Jan. A. . Zienkiewicz, Karolina Kaldunska, Katarzyna Fedoruk, Antonio J. Barros dos Santos, Mariusz Stefanski, Waldeci Paraguassu, Tadeusz M. Muziol, Maciej Ptak
Summary: The synthesis and investigation of a novel one-dimensional hybrid organic-inorganic perovskitoid templated by the 1,1,1-trimethylhydrazinium cation are reported. The material undergoes phase transitions at different temperatures and pressures, which are related to changes in structure and cation arrangement. Optical studies reveal its wide band gap and ability to emit excitonic emission.
INORGANIC CHEMISTRY
(2022)
Article
Physics, Multidisciplinary
Anubhab Dey, Nathan Cottam, Oleg Makarovskiy, Wenjing Yan, Vaidotas Miseikis, Camilla Coletti, James Kerfoot, Vladimir Korolkov, Laurence Eaves, Jasper F. Linnartz, Arwin Kool, Steffen Wiedmann, Amalia Patane
Summary: Researchers discovered the quantum Hall effect in graphene encapsulated by the ferroelectric insulator CuInP2S6, which is significant for compact resistance standards that can operate at room temperature.
COMMUNICATIONS PHYSICS
(2023)
Article
Multidisciplinary Sciences
Juan C. Criado, Sebastian Schenk, Michael Spannowsky, Peter D. Hatton, L. A. Turnbull
Summary: In this study, we investigate the properties of anti-skyrmions, the counterparty of skyrmions with opposite topological charge, using Monte Carlo simulations. We find that a combination of ferromagnetic exchange and Dzyaloshinskii-Moriya interactions can stabilize different types of skyrmions. Furthermore, we present a finite-temperature phase diagram that shows the existence of a stable anti-skyrmion lattice phase within a certain temperature range.
SCIENTIFIC REPORTS
(2022)
Article
Materials Science, Multidisciplinary
Natalia V. Morozova, Aleksandr Yu. Usik, Igor V. Korobeinikov, Alexander N. Titov, Sergey V. Ovsyannikov
Summary: A semiconductor-metal transition was observed in Cu-intercalated TiSe2 single crystals (x <= 0.1) at room temperature under mechanical stress. The crystals can be transformed from semiconductors to metals by applying a stress of 1-3 GPa. This suggests the potential application of CuxTiSe2 crystals in optoelectronic micro-devices where their characteristics can be controlled by stress or strain.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Chemistry, Multidisciplinary
Ya-Di Zhang, Le Ye, Na Wang, Le-Ping Miao, Heng-Yun Ye, Chao Shi
Summary: New hybrid nitrate perovskites with structural diversity and tunable ferroelectricity have been synthesized, providing a promising platform for achieving novel properties and potential applications.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Physics, Multidisciplinary
Lin Wang, Ignacio Gutierrez-Lezama, Celine Barreteau, Dong-Keun Ki, Enrico Giannini, Alberto F. Morpurgo
PHYSICAL REVIEW LETTERS
(2016)
Article
Physics, Multidisciplinary
Zhe Wang, Dong-Keun Ki, Jun Yong Khoo, Diego Mauro, Helmuth Berger, Leonid S. Levitov, Alberto F. Morpurgo
Article
Materials Science, Multidisciplinary
Youngwoo Nam, Dong-Keun Ki, Mikito Koshino, Edward McCann, Alberto F. Morpurgo
Article
Physics, Multidisciplinary
Youngwoo Nam, Dong-Keun Ki, David Soler-Delgado, Alberto F. Morpurgo
Article
Physics, Multidisciplinary
L. Wang, N. Chepiga, D-K. Ki, L. Li, F. Li, W. Zhu, Y. Kato, O. S. Ovchinnikova, F. Mila, I. Martin, D. Mandrus, A. F. Morpurgo
PHYSICAL REVIEW LETTERS
(2017)
Article
Chemistry, Multidisciplinary
Mojun Chen, Jihyuk Yang, Zhenyu Wang, Zhaoyi Xu, Heekwon Lee, Hyeonseok Lee, Zhiwen Zhou, Shien-Ping Feng, Sanghyeon Lee, Jaeyeon Pyo, Seung Kwon Seol, Dong-Kenn Ki, Ji Tae Kim
ADVANCED MATERIALS
(2019)
Article
Chemistry, Physical
Rashad Rashid, Francis Chi-Chung Ling, Shuang-Peng Wang, Ke Xiao, Xiaodong Cui, Qing Rao, Dong-Keun Ki
Summary: This study demonstrates the successful catalyst-free CVD growth of beta and gamma phase In2Se3 flakes with thicknesses down to only a few nanometers, and thoroughly investigates their structural, optical, and ferroelectric properties. The observation of ferroelectricity in gamma-In2Se3 without the need for a catalyst could be a valuable addition in the field of ferroelectric and piezoelectric switching devices.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Nanoscience & Nanotechnology
Peng Yang, Jiajia Zha, Guoyun Gao, Long Zheng, Haoxin Huang, Yunpeng Xia, Songcen Xu, Tengfei Xiong, Zhuomin Zhang, Zhengbao Yang, Ye Chen, Dong-Keun Ki, Juin J. Liou, Wugang Liao, Chaoliang Tan
Summary: The lack of stable p-type van der Waals (vdW) semiconductors has been a major barrier for the development of low-dimensional materials in the industry. In this study, high-quality Te nanobelts were grown on atomically flat hexagonal boron nitride (h-BN) substrate, enabling the fabrication of high-performance p-type field-effect transistors (FETs). The Te-based FET showed an ultrahigh hole mobility at room temperature, which holds great potential for future high-performance p-type 2D FETs and metal-oxide-semiconductor (p-MOS) inverters.
NANO-MICRO LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Jing Yu, Guoyun Gao, Wei Han, Changting Wei, Yueyang Wang, Tianxiang Lin, Tianyu Zhang, Zhi Zheng, Dong-Keun Ki, Hongyuan Zhang, Man Ho Ng, Hang Liu, Shuangpeng Wang, Hao Wang, Francis Chi-Chung Ling
Summary: This study reports a method for preparing wafer-scale (Ga, Cu) co-doping ZnO films with super-high dielectric constant and good homogeneity. The research found that the dielectric constant can vary over a wide range by adjusting the co-doping concentration. Experimental results also demonstrated that the Al2O3 / GCZO gate dielectric stack is suitable for 2D electronic devices and has advantages in terms of compatibility to CMOS processes and fabrication of high-performance electronic devices over conventional dielectrics.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Heekwon Lee, Zhuoran Wang, Qing Rao, Sanghyeon Lee, Xiao Huan, Yu Liu, Jihyuk Yang, Mojun Chen, Dong-Keun Ki, Ji Tae Kim
Summary: This article reports a 3D printed micro-thermoelectric device that allows for direct 4D thermometry at the microscale. The device consists of freestanding thermocouple probe networks fabricated by bi-metal 3D printing, with excellent spatial resolution. It demonstrates that the developed 4D thermometry can explore the dynamics of heating and cooling processes on microscale subjects such as microelectrodes or water meniscus. The use of 3D printing opens up possibilities for realizing a wide range of on-chip, freestanding microsensors or microelectronic devices without design restrictions by manufacturing processes.
ADVANCED MATERIALS
(2023)