Review
Chemistry, Multidisciplinary
Kaichen Xie, Xiaosong Li, Ting Cao
Summary: Recent studies on the optical properties of 2D materials have revealed unique phenomena and features that arise from the nature of two- and multi-particle excited states. The theory, modeling, and ab initio calculations of these optically excited states have been reviewed, with different analytical and ab initio approaches compared to reveal their strengths and limitations. The understanding of optically excited states in 2D materials is crucial for both fundamental scientific research and future developments in quantum information science and nano-photonics.
ADVANCED MATERIALS
(2021)
Article
Physics, Multidisciplinary
Vamshi M. Katukuri, Nikolay A. Bogdanov, Ali Alavi
Summary: The discovery of superconductivity in hole-doped infinite-layer NdNiO2 has reinvigorated the study of unconventional superconductivity. By using advanced quantum chemistry methods, we investigated the electron removal states in NdNiO2 and found that the hole-doped d(8) ground state is different from the isostructural cuprate analog. The analysis shows that the doped hole mainly localizes on the Ni 3d(x2-y2) orbital to form a closed-shell singlet in NdNiO2. Furthermore, we quantified the different types of electronic correlations in both NdNiO2 and cuprate compounds and found that the dynamic radial-type correlations within the Ni d manifold are persistent in hole-doped NdNiO2.
FRONTIERS IN PHYSICS
(2022)
Article
Physics, Condensed Matter
T. Bryk, I-m Ilenkov, A. P. Seitsonen
Summary: We performed ab initio simulation and theoretical study on collective dynamics in liquid Sb at 973 K. By applying the GCM theoretical approach to analysis of simulation-derived time correlation functions, we identified two types of propagating eigenmodes. We found that the flat dispersion of the high-frequency branch of propagating modes can be explained by out-of-phase oscillations of nearest neighbors forming quasi-bound atomic pairs for at least 30 ps. We discussed the collective dynamics features in non-simple metallic melts containing quasi-bound pairs.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Chemistry, Multidisciplinary
Ying Xu, Xiaoyu Xuan, Tingfan Yang, Zhuhua Zhang, Si-Dian Li, Wanlin Guo
Summary: The bilayer borophene on Ag(111) has the same ground state and semiconductor properties as its freestanding counterpart, and it can partially decouple from the substrate.
Article
Chemistry, Multidisciplinary
Sheqiang Han, Xiaodong Zhang, Qi Song, Bo Zhou, Shangwu Fan
Summary: Ammonium-ion batteries (AIBs) have gained significant attention as potential energy storage systems due to their lightweight, safety, affordability, and wide availability. Finding a fast ammonium ion conductor for AIB electrodes, which directly impacts the battery's electrochemical performance, is of great importance. Using high-throughput bond-valence calculation, we screened more than 8000 compounds in the ICSD database and identified 27 candidate electrode materials with low diffusion barriers for AIBs. These materials were further analyzed for their electrochemical properties. Our findings, which establish the relationship between structure and electrochemical properties of important electrode materials for AIBs development, could pave the way for next-generation energy storage systems.
Article
Spectroscopy
ShuaiShuai Liu, Guangbao Wang, Ya Li, Xucheng Li, Wuyin Huang, Eryin Feng
Summary: The feasibility of laser cooling BN- anion was theoretically investigated, and ab initio calculations were performed on three low-lying states with good agreement with available data. A cooling scheme using three laser beams was proposed, and population dynamics were studied with the rate equation approach, showing promising results for stopping the BN- anion molecule in a cryogenic beam.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2021)
Article
Chemistry, Physical
Fausto Cargnoni
Summary: We investigated the electronic structure of the C-He complex, studying both the ground and excited states. The interaction potentials were computed using the MultiReference Configurations-Interaction level of theory, and our results compared well with existing data for the ground state. We also determined rovibrational bound states and transition dipole moments, providing a comprehensive understanding of the interaction between excited carbon atoms and helium, which has implications in astrophysics and terrestrial experiments.
CHEMICAL PHYSICS LETTERS
(2023)
Article
Optics
Tevin Ding, Daniel Lin, Guowen Ding
Summary: This article discusses the effect of deposition conditions on the properties of nanostructural materials, particularly the refractive index of thin-metal alloys. By deriving a model based on the properties of the alloy's main elements, the refractive index of untested alloys under specific deposition conditions can be accurately predicted.
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
(2023)
Article
Computer Science, Interdisciplinary Applications
Anup Kumar Mandia, Bhaskaran Muralidharan, Jung-Hae Choi, Seung-Cheol Lee, Satadeep Bhattacharjee
Summary: The module calculates the mobility and conductivity of semiconducting materials using Rode's algorithm with good agreement to experimental results, and shows favorable improvement compared to the RTA method.
COMPUTER PHYSICS COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Y. Ammari, E. K. Hlil
Summary: In this study, the structural, electronic, and optical properties of nitride ternary phase CaNiN containing nickel (I) and calcium were investigated using density functional theory. It was found that the non-spin polarized state is more stable, and Dirac-cones-like band crossings were observed in the band structure. The study also utilized many-body perturbation theory to analyze optical properties of the compound.
Article
Chemistry, Physical
Zsuzsanna Koczor-Benda, Teodora Mateeva, Edina Rosta
Summary: In this study, a binless formulation of the dynamic weighted histogram analysis method (DHAM) is proposed, which can be used for high-dimensional and Hamiltonian-based biasing to enhance sampling of electron transfer processes. By comparing with classical simulations and quantum chemistry calculations, it is found that this method can accurately predict the rates of electron transfer reactions.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Jack McArthur, Marina R. Filip, Diana Y. Qiu
Summary: In this study, a new approximation method called IPSA-2C is developed for calculating excited states in layered hybrid organic-inorganic lead halide perovskites. By separating the polarizability of the organic/inorganic layers into minimal building blocks, IPSA-2C method avoids the undesirable power-law scaling. It accurately reproduces the quasi-particle band structures and absorption spectra for a series of Ruddlesden-Popper perovskites, shedding light on the screening effects between the organic and inorganic sublattices.
Article
Chemistry, Physical
Chad E. Hoyer, Lixin Lu, Hang Hu, Kirill D. Shumilov, Shichao Sun, Stefan Knecht, Xiaosong Li
Summary: In this study, a correlated Dirac-Coulomb-Breit multiconfigurational self-consistent-field method is introduced within the frameworks of complete active space and density matrix renormalization group. The Dirac-Coulomb-Breit Hamiltonian is included variationally in both the mean-field and correlated electron treatment. The importance of the Breit operator in electron correlation and the rotation between the positive-and negative-orbital space in the no-virtual-pair approximation is also analyzed. Fine-structure splittings and lanthanide contraction in diatomic fluorides are used as benchmark studies to understand the contribution from the Breit correlation.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Multidisciplinary Sciences
Leonid Pourovskii, Sergii Khmelevskyi
Summary: This passage discusses the nature of order in low-temperature phases of certain materials and the hidden orders that may spark research interest. By studying neptunium dioxide NpO2, it is found that the ground-state order and magnetic excitations can be fully described by a low-energy Hamiltonian, revealing the multipolar exchange mechanism behind the anomalous volume contraction of the NpO2 HO phase.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Chemistry, Physical
Juqin Zeng, Michele Re Fiorentin, Marco Fontana, Micaela Castellino, Francesca Risplendi, Adriano Sacco, Giancarlo Cicero, M. Amin Farkhondehfal, Filippo Drago, Candido F. Pirri
Summary: In this study, a SbCu2O material was synthesized via one-pot microwave-assisted solvothermal route and its catalytic performance in electrochemical reduction of CO2 was investigated. The Sb-Cu2O bimetallic catalyst exhibited high CO selectivity and good stability.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Physics, Multidisciplinary
Nikolay A. Bogdanov, Giovanni Li Manni, Sandeep Sharma, Olle Gunnarsson, Ali Alavi
Summary: Cuprates exhibit exotic states due to the interplay between spin, charge, and orbital degrees of freedom. Ab initio calculations reveal that the orbital expansion mechanism plays a key role in the magnetic properties of cuprates. Additionally, the electronic properties of cuprates are highly sensitive to the presence and displacement of apical oxygens perpendicular to the CuO2 planes, influencing the nearest-neighbour superexchange antiferromagnetic coupling.
Article
Physics, Multidisciplinary
Vamshi M. Katukuri, Nikolay A. Bogdanov, Ali Alavi
Summary: The discovery of superconductivity in hole-doped infinite-layer NdNiO2 has reinvigorated the study of unconventional superconductivity. By using advanced quantum chemistry methods, we investigated the electron removal states in NdNiO2 and found that the hole-doped d(8) ground state is different from the isostructural cuprate analog. The analysis shows that the doped hole mainly localizes on the Ni 3d(x2-y2) orbital to form a closed-shell singlet in NdNiO2. Furthermore, we quantified the different types of electronic correlations in both NdNiO2 and cuprate compounds and found that the dynamic radial-type correlations within the Ni d manifold are persistent in hole-doped NdNiO2.
FRONTIERS IN PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Yaqian Guo, Hui Liu, Oleg Janson, Ion Cosma Fulga, Jeroen van den Brink, Jorge I. Facio
Summary: It has been discovered that collinear antiferromagnets, depending on their symmetries, can break the spin degeneracy in momentum space without spin-orbit coupling. These systems, known as altermagnets, are characterized by a spin-momentum texture determined by crystal and magnetic structure. This study focuses on q = 0 antiferromagnetic compounds in the MAGNDATA database and introduces numerical measures for average momentum-space spin splitting, analyzing over sixty compounds including CoF2, FeSO4F, LiFe2F6, RuO2, CrNb4S8, and CrSb.
MATERIALS TODAY PHYSICS
(2023)
Article
Multidisciplinary Sciences
Hiroki Ueda, Mirian Garcia-Fernandez, Stefano Agrestini, Carl P. Romao, Jeroen van den Brink, Nicola A. Spaldin, Ke-Jin Zhou, Urs Staub
Summary: The concept of chirality plays a crucial role in various natural phenomena. Recent studies in condensed matter physics have revealed the existence of chiral fermions and their connection to emergent phenomena and topology. However, experimental verification of chiral phonons in macroscopic systems remains challenging. In this study, we provide experimental evidence of chiral phonons using resonant inelastic X-ray scattering with circularly polarized X-rays. By studying the chiral material quartz, we demonstrate that circularly polarized X-rays couple to chiral phonons at specific positions in reciprocal space, allowing for the determination of the chiral dispersion of lattice modes. This experimental proof of chiral phonons introduces a new degree of freedom in condensed matter physics, with both fundamental importance and potential for exploring novel emergent phenomena based on chiral bosons.
Article
Materials Science, Multidisciplinary
Dennis Wawrzik, Jorge I. Facio, Jeroen van den Brink
Summary: In recent years, the concept of electronic Berry curvature (BC) has been recognized as crucial for understanding and predicting physical properties of crystalline materials. While non-magnetic materials with inversion symmetry have a strictly zero BC in their bulk, we demonstrate that a finite BC can emerge at their surfaces and interfaces, resulting in Hall-type transport responses. Through first principles calculations, we observe the presence of a surface Berry curvature dipole and associated quantum nonlinear Hall effects at various symmetries of bismuth, mercury-telluride (HgTe), and rhodium surfaces. This discovery opens up a wide range of materials to explore and harness the physical effects arising from electronic Berry curvature exclusively at their boundaries.
MATERIALS TODAY PHYSICS
(2023)
Article
Physics, Applied
Rakshanda Dhawan, Vikrant Chaudhary, Chandan Kumar Vishwakarma, Mohd Zeeshan, Tashi Nautiyal, Jeroen van den Brink, Hem C. Kandpal
Summary: Anomalous carrier transport in magnetic Heusler compounds has attracted significant attention due to their unique band structure and broken time-reversal symmetry. In this study, we investigate the properties of CoFeSn and propose a cubic polymorph based on structural stability, lattice dynamics, and magnetic analysis. Utilizing density-functional-theory calculations, we predict that cubic CoFeSn exhibits robust half-metallic ferromagnetic behavior with a high Curie temperature and significant spin Hall conductivity. We also find that adjusting the Fermi level can enhance the anomalous Hall conductivity or spin Hall conductivity. Our findings provide important insights for the realization of quantum anomalous and spin Hall effects in half-Heusler compounds.
APPLIED PHYSICS LETTERS
(2023)
Article
Multidisciplinary Sciences
Wuyang Ren, Wenhua Xue, Shuping Guo, Ran He, Liangzi Deng, Shaowei Song, Andrei Sotnikov, Kornelius Nielsch, Jeroen van den Brink, Guanhui Gao, Shuo Chen, Yimo Han, Jiang Wu, Ching-Wu Chu, Zhiming Wang, Yumei Wang, Zhifeng Ren
Summary: Studies have shown that vacancy-mediated anomalous transport properties are flourishing in various fields due to their fascinating effects on photoelectric, ferroelectric, and spin-electric behaviors in solid materials. In this study, the authors reveal the multifunctionality of vacancy in tailoring the transport properties of a defective half-Heusler ZrNiBi material, providing insights into the phononic and electronic transport processes. These findings not only demonstrate the potential of this thermoelectric material but also promote further exploration of vacancy-mediated transport properties.
NATURE COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Pritam Bhattacharyya, Nikolay A. Bogdanov, Satoshi Nishimoto, Stephen D. Wilson, Liviu Hozoi
Summary: The Kitaev exchange in triangular-lattice materials is found to be antiferromagnetic, in contrast to the ferromagnetic behavior in honeycomb compounds. This discovery provides a new explanation for the experimentally observed quantum spin liquid and reveals the factors that influence the exchange paths and effective coupling parameters.
NPJ QUANTUM MATERIALS
(2023)
Article
Physics, Multidisciplinary
Carmine Ortix, Jeroen van den Brink
Summary: Magnetoelectric crystals have the ability to convert electric fields into magnetic polarizations and magnetic fields into ferroelectric polarizations. In this study, a new method is proposed to achieve linear magnetoelectric coupling in ferromagnetic insulators using nanoscale curved geometries and intrinsic Dzyaloshinskii-Moriya interaction (DMI). The reorganization of the magnetic texture induced by the combination of curved geometries and DMI breaks inversion symmetry and creates macroscopic magnetoelectric multipoles. This study demonstrates the activation of a magnetoelectric monopole in two-dimensional magnets through controlled ripples and the direct linear magnetoelectric coupling in zigzag-shaped ferromagnetic wires.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Materials Science, Multidisciplinary
Viktor Koenye, Lotte Mertens, Corentin Morice, Dmitry Chernyavsky, Ali G. Moghaddam, Jasper van Wezel, Jeroen van den Brink
Summary: We demonstrate that tilted Weyl semimetals with spatially varying tilt can be used to study anisotropic optics and curved spacetime. By examining specific tilting configurations, we numerically analyze the time evolution of electronic wave packets and current densities. Our results show that electron trajectories in such systems can be determined using Fermat's principle with an inhomogeneous, anisotropic effective refractive index. Additionally, we show that these systems can simulate gravitational lensing around a synthetic black hole, revealing gravitational features.
Article
Physics, Multidisciplinary
Ayushi Singhania, Jeroen van den Brink, Satoshi Nishimoto
Summary: This study investigates the interplay of disorder and Heisenberg interactions in the Kitaev model on a honeycomb lattice. The effects of disorder on the transition between Kitaev spin liquid and magnetic ordered states as well as the stability of magnetic ordering are examined. The results show that disorder reduces the range of spin-liquid phases and changes the transitions to magnetic ordered phases to a more crossoverlike behavior. In addition, long-range orderings in the clean system are replaced by domains with different ordering directions.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Materials Science, Multidisciplinary
Shruti Agarwal, Shreekant Gawande, Satoshi Nishimoto, Jeroen Van den Brink, Sanjeev Kumar
Summary: Using a combination of mean-field Bogoliubov-de Gennes approach and density matrix renormalization group method, we discovered first-order topological transitions between topological superconducting and trivial insulating phases in a sawtooth lattice of intersite attractive fermions. The topological properties of different phases were characterized in terms of winding numbers, Majorana edge modes, and entanglement spectra. By studying the effect of disorder on first-order topological phase transitions, we established disorder-induced topological phase coexistence as a mechanism for generating a finite density of Majorana particles.
Article
Physics, Multidisciplinary
Viktor Koenye, Corentin Morice, Dmitry Chernyavsky, Ali G. Moghaddam, Jeroen van den Brink, Jasper van Wezel
Summary: In this study, we simulate the dynamics of massless Dirac fermions in curved space-times with one, two, and three spatial dimensions by constructing tight-binding Hamiltonians with spatially varying hoppings. These models represent tilted Weyl semimetals where the tilting varies with position, similar to the light cones near the horizon of a black hole. We demonstrate the gravitational analogies in these models by numerically evaluating the propagation of wave packets on the lattice and comparing them to the geodesics of the corresponding curved space-time. We also show that the motion of electrons in these spatially varying systems can be understood through the conservation of energy and the quasiconservation of quasimomentum. Furthermore, we reveal that horizons in the lattice models can be constructed with finite energies using specially designed tilting profiles.
PHYSICAL REVIEW RESEARCH
(2022)
Article
Physics, Multidisciplinary
Gabriele Naselli, Ali G. Moghaddam, Solange Di Napoli, Veronica Vildosola, Ion Cosma Fulga, Jeroen van den Brink, Jorge I. Facio
Summary: We analyze the electronic structure of topological surface states in the family of magnetic topological insulators. We show that, at the magnetic ordering temperature, the symmetry of the Dirac cone warping changes from hexagonal to trigonal, leading to energy splitting between surface states. This energy splitting can be used as a simple protocol to detect magnetic ordering via the surface electronic structure.
PHYSICAL REVIEW RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Shiang Fang, Linda Ye, Madhav Prasad Ghimire, Mingu Kang, Junwei Liu, Minyong Han, Liang Fu, Manuel Richter, Jeroen van den Brink, Efthimios Kaxiras, Riccardo Comin, Joseph G. Checkelsky
Summary: In this study, we investigated the electronic structure of the ferromagnetic kagome metal Fe3Sn2 without spin-orbit coupling. We found two energetically split helical nodal lines near K and K' in the Brillouin zone, resulting from the trigonal stacking of the kagome layers. The hopping across A-A stacking introduced energy splitting, while that across A-B stacking controlled the momentum space amplitude of the helical nodal lines. Our findings have important implications for the design of topological materials.
