Results 81 to 90 of about 19,877 (264)

High‐Entropy Engineering and External Magnetic Field Modulation Synergistically Enhance the H2S Sensing Performance of Rare‐Earth Perovskite Ferrites

Advanced Science, EarlyView.
A novel high‐entropy perovskite oxide, (Gd0.2Tb0.2Dy0.2Ho0.2Er0.2)FeO3, was successfully synthesized for advanced hydrogen sulfide gas detection. By synergistically coupling high‐entropy‐induced local lattice distortion with weak magnetic field modulation, the tailored material generates abundant active sites. This innovative dual strategy dramatically
Yunfei Wang, Min Zhang, Rui Li, Xiaolong Yao, Zhaofeng Wu, Fengdong Qu, Shan Qiu, Zhenjiang Li   +7 more
wiley   +1 more source

Electronic spectrum and superconductivity in Hubbard model

Condensed Matter Physics, 2008
A microscopic theory of electronic spectrum and superconducting pairing within the Hubbard model is formulated. The Dyson equation for the normal and anomalous Green functions in terms of the Hubbard operators is derived by applying the Mori-type ...
N.M. Plakida, V.S. Oudovenko
doaj   +1 more source

Exact Ground States for Quasi 1D Systems with Hubbard Interaction [PDF]

Журнал нано- та електронної фізики, 2012
Using a positive semidefinite operator technique we deduced exact ground states for a modified diamond chain described by a non-integrable Hubbard model with on-site repulsion.
Zs. Gulácsi, E. Kovács
doaj  

Atomically Modulating Competing Exchange Interactions in Centrosymmetric Skyrmion Hosts GdRu2X2 (X = Si and Ge)

Advanced Electronic Materials, EarlyView.
Our work bridges the gap between skyrmion discovery and material design by demonstrating how atomic‐scale control of exchange interactions enables tunable skyrmion phase transitions in centrosymmetric magnetic metals. ABSTRACT Magnetic skyrmions are topologically protected spin states that hold promise for shaping the future of electronics.
Dasuni N. Rathnaweera, Xudong Huai, K. Ramesh Kumar, Michał J. Winiarski, Tomasz Klimczuk, Allana G. Iwanicki, Satya K. Kushwaha, Martin Mourigal, Tyrel M. McQueen, Thao T. Tran   +9 more
wiley   +1 more source

Machine learning Hubbard parameters with equivariant neural networks

npj Computational Materials
Density-functional theory with extended Hubbard functionals (DFT + U + V) provides a robust framework to accurately describe complex materials containing transition-metal or rare-earth elements.
Martin Uhrin, Austin Zadoks, Luca Binci, Nicola Marzari, Iurii Timrov   +4 more
doaj   +1 more source

Zero Modes and Global Antiferromagnetism in Strained Graphene

Physical Review X, 2014
A novel magnetic ground state is reported for the Hubbard Hamiltonian in strained graphene. When the chemical potential lies close to the Dirac point, the ground state exhibits locally both the Néel and ferromagnetic orders, even for weak Hubbard ...
Bitan Roy, Fakher F. Assaad, Igor F. Herbut   +2 more
doaj   +1 more source

Electric Field‐Induced Hole‐ and Electron‐Type Flat Bands in Twisted Double Bilayer Graphene

Advanced Electronic Materials, EarlyView.
The electronic structure of twisted double bilayer graphene is visualized using angle‐resolved photoemission spectroscopy with micrometer spatial resolution at twists of 3.1∘$^\circ$ and 6.0∘$^\circ$ as a function of gate voltage. Tunable hybridization effects and flat band formation occurs between valence and conduction band states due to a finite ...
Zhihao Jiang, Dongkyu Lee, Alfred J. H. Jones, Youngju Park, Paulina Majchrzak, Kimberly Hsieh, Chakradhar Sahoo, Thomas S. Nielsen, Kenji Watanabe, Takashi Taniguchi, Philip Hofmann, Yong P. Chen, Jeil Jung, Søren Ulstrup   +13 more
wiley   +1 more source

Decoding Gas Evolution Pathways and Interfacial Chemistry in Layered Oxide Cathodes for Safer Sodium‐Ion Batteries

Advanced Energy Materials, EarlyView.
Gas evolution behaviors of sodium layered oxide cathodes with varying compositions, cutoff voltages, dopants, and particle sizes/morphologies have been systematically investigated by online electrochemical mass spectrometry. The fundamental outgassing mechanisms of sodium‐based cathodes compared to lithium‐based cathodes have been elucidated.
Chen Liu, Zehao Cui, Arumugam Manthiram
wiley   +1 more source

Prediction of Structural Stability of Layered Oxide Cathode Materials: Combination of Machine Learning and Ab Initio Thermodynamics

Advanced Energy Materials, EarlyView.
In this work, we developed a phase‐stability predictor by combining machine learning and ab initio thermodynamics approaches, and identified the key factors determining the favorable phase for a given composition. Specifically, a lower TM ionic potential, higher Na content, and higher mixing entropy favor the O3 phase.
Liang‐Ting Wu, Milica Zdravković, Dijana Milosavljević, Konstantin Köster, Olivier Guillon, Jyh‐Chiang Jiang, Payam Kaghazchi   +6 more
wiley   +1 more source

Thermodynamics of the metal-insulator transition in the extended Hubbard model

SciPost Physics, 2019
In contrast to the Hubbard model, the extended Hubbard model, which additionally accounts for non-local interactions, lacks systemic studies of thermodynamic properties especially across the metal-insulator transition.
Malte Schüler, Erik G. C. P. van Loon, Mikhail I. Katsnelson, Tim O. Wehling
doaj   +1 more source