Article
Multidisciplinary Sciences
Yigeng Peng, Tong Wu, Guanglu Yuan, Lihan Chi, Shicheng Jiang, Konstantin Dorfman, Chao Yu, Ruifeng Lu
Summary: High harmonic generation from solid-state crystals in strong laser fields is understood based on the band structure and periodic boundary conditions. A quasi-band model is developed for a ring-type cluster of cyclo[18]carbon, which predicts solid state-like HHG in this system. Under linearly polarized laser field, cyclo[18]carbon exhibits solid state-like HHG originating from intraband oscillations and interband transitions, providing a potential method to detect molecular or material structures optically. The results are in good agreement with time-dependent density functional theory calculations and contribute to connecting the physics of HHG in gases and solids.
Article
Chemistry, Multidisciplinary
Daniel Wines, Kamal Choudhary, Adam J. Biacchi, Kevin F. Garrity, Francesca Tavazza
Summary: High-throughput DFT calculations were employed to systematically search for conventional superconductors, including two-dimensional (2D) materials. Over 1000 2D materials in the JARVIS-DFT database were screened, and electron-phonon coupling calculations were performed to determine the superconducting transition temperature (Tc) for 165 materials. Among them, 34 dynamically stable structures with Tc above 5 K were identified, including previously unreported Mg2B4N2 (Tc = 21.8 K). Experimental measurements of selected layered superconductors were also conducted and discussed within the context of DFT results. The workflow outcomes provide a roadmap for future computational and experimental studies of new and emerging 2D superconductors.
Review
Materials Science, Multidisciplinary
Kaleem Ullah, Yafei Meng, Yi Shi, Fengqiu Wang
Summary: This paper reviews the state-of-the-art advances in harmonic generation in emerging two-dimensional materials and provides the criteria of chiral selection rules for the second and third harmonic generations. Different strategies to tune and enhance harmonic generation in two-dimensional materials are also discussed.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Christian Heide, Yuki Kobayashi, Amalya C. Johnson, Tony F. Heinz, David A. Reis, Fang Liu, Shambhu Ghimire
Summary: We report the layer-by-layer build-up of high-order harmonic generation (HHG) in artificially stacked transition metal dichalcogenides (TMDC) crystals. High-order harmonics up to the 19th order are generated by the interaction with a mid-infrared (MIR) driving laser. The generation of harmonics is sensitive to the number of layers and their relative orientation, with different stacking configurations showing different harmonic intensities.
Article
Chemistry, Multidisciplinary
Jun Cai, Zheng Sun, Peng Wu, Rahul Tripathi, Hao-Yu Lan, Jing Kong, Zhihong Chen, Joerg Appenzeller
Summary: This article investigates the polarity and current tuning methods of MoTe2 materials. They found that the MoTe2 FETs, which have not been exposed to air for a long time, are n-type regardless of the metal contact type. For p-type FETs, they introduced a novel nitric oxide doping strategy. By doping only in the contact region, they achieved a controlled transition of MoTe2 FETs from n-type to unipolar p-type. Finally, they demonstrated a complementary inverter circuit based on high-performance n-type and p-type FETs of MoTe2.
Article
Optics
Gia Quyet Ngo, Emad Najafidehaghani, Ziyang Gan, Sara Khazaee, Malte Per Siems, Antony George, Erik P. Schartner, Stefan Nolte, Heike Ebendorff-Heidepriem, Thomas Pertsch, Alessandro Tuniz, Markus A. Schmidt, Ulf Peschel, Andrey Turchanin, Falk Eilenberger
Summary: This study demonstrates a method to achieve second-harmonic generation in functionalized optical fibers by directly growing highly nonlinear MoS2 monolayers on the fiber's core. The approach is scalable and can be generalized to other materials and waveguide systems.
Article
Optics
Bumho Kim, Jicheng Jin, Zhi Wang, Li He, Thomas Christensen, Eugene J. Mele, Bo Zhen
Summary: Researchers have achieved three-dimensional nonlinear optical materials by precisely controlling and twisting individual two-dimensional van der Waals interfaces. By adding pseudo-screw symmetries to WS2 stacks, new nonlinear crystals with fundamentally different properties from natural WS2 have been realized. The size of the newly enabled nonlinearity can be enhanced by controlling the number of interfaces and the excitation wavelength.
Article
Physics, Fluids & Plasmas
Weijian Jiao, Stefano Gonella
Summary: In this study, experimental evidence of nonlinear wave propagation in a triangular lattice of repulsive magnets supported by an elastic foundation of thin pillars is provided. The individual features of the nonlinear wave field are interpreted through a phonon band calculation that accounts for interparticle repulsive forces. The presence of two spectrally distinct components in the wave response induced by second harmonic generation demonstrates the lattice's capability for functional enrichment through nonlinear mechanisms.
Article
Materials Science, Multidisciplinary
Frederico B. Sousa, Lucas Lafeta, Alisson R. Cadore, Prasana K. Sahoo, Leandro M. Malard
Summary: The interface between different semiconductors is crucial in determining electronic properties at the heterojunction. Recent research shows that two-dimensional transition metal dichalcogenides have sharp interfaces that can be used in next-generation optoelectronic devices. Second harmonic generation (SHG) can be used to reveal these sharp interfaces in lateral heterostructures, demonstrating that SHG microscopy is a sensitive technique for uncovering nanoscale features in layered materials and their heterostructures.
Article
Engineering, Environmental
P. L. Taberna, J. Barros Barbosa, A. Balocchi, I. Gerber, K. Urita, A. Barnabe, X. Marie, J. Y. Chane-Ching
Summary: 2D photoactive materials have potential for use in photocatalytic devices by enhancing light absorption and charge carrier transport. Hetero-structure nanoporous networks with patch-like coatings show promise for improving the performance of photo-catalysts, particularly in terms of defect passivation and charge transfer.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Multidisciplinary Sciences
Fu-Xiang Rikudo Chen, Chia-Yu Lin, Hui-Ying Siao, Cheng-Yuan Jian, Yong-Cheng Yang, Chun-Liang Lin
Summary: In this study, a deep learning-based atomic defect detection framework (DL-ADD) is proposed to efficiently detect atomic defects in molybdenum disulfide (MoS2) and generalize the model for defect detection in other TMD materials.
Article
Chemistry, Multidisciplinary
Seon Namgung, Steven J. Koester, Sang-Hyun Oh
Summary: This study demonstrates an ultraflat nanogap platform based on atomic layer deposition for fabricating 2D material-based optical and electronic devices. Short-channel field-effect transistors based on black phosphorus and MoS2, as well as photodetectors with a nanoscale photosensitive channel, were successfully fabricated on this platform, showing higher photosensitivity compared to microscale gap channels.
Article
Physics, Multidisciplinary
Ya Bai, Fucong Fei, Shuo Wang, Na Li, Xiaolu Li, Fengqi Song, Ruxin Li, Zhizhan Xu, Peng Liu
Summary: Three-dimensional topological insulators host unique spin-polarized surface states with no energy gap, exhibiting unconventional charge and spin transport properties. High harmonic generation from the intrinsic topological insulator BiSbTeSe2 reveals that even-order harmonics polarized along the pump polarization stem from the spin current in helical surface states, while perpendicular components originate from out-of-plane spin polarization related to hexagonal wrapping effect.
Article
Chemistry, Multidisciplinary
Yuan Zhang, Yangchun Tan, Yangda Dong, Liyufeng Dai, Chuanlai Ren, Fengyuan Zhang, Lingping Zeng, Feng An, Changjian Li, Boyuan Huang, Gaokuo Zhong, Jiangyu Li
Summary: The Materials Genome Initiative aims to accelerate the discovery, development, manufacture, and deployment of advanced materials. This study introduces a high-throughput scanning second-harmonic-generation microscope that enables rapid screening and probing of polar materials. The technique is applied to investigate ferroelectrics and demonstrate its high-throughput capabilities using compositional-gradient and thickness-gradient films.
ADVANCED MATERIALS
(2023)
Article
Physics, Multidisciplinary
Jia-Qi Liu, Xue-Bin Bian
Summary: Studying high-order harmonic generation in Fibonacci quasicrystals reveals the presence of multi-channel emissions with higher yield and broader spectral range compared to crystals, paving the way for understanding and controlling HHG in quasicrystals and potentially leading to a shorter and stronger attosecond light source based on compact solids.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Shuyi Liu, Franco P. Bonafe, Heiko Appel, Angel Rubio, Martin Wolf, Takashi Kumagai
Summary: In this study, we use low-temperature optical scanning tunneling microscopy and inelastic light scattering to investigate the plasmonic properties of a picocavity near a single-atom quantum point contact (QPC). We find that the vibration mode localized at the single Ag adatom on the Ag(111) surface undergoes a sharp change upon QPC formation. Density functional theory simulations reveal that the atomic-scale structural relaxation at the QPC leads to a discrete change in the plasmonic field strength, volume, distribution, and vibration mode.
Article
Chemistry, Physical
Jason Kaye, Alex Barnett, Leslie Greengard, Umberto De Giovannini, Angel Rubio
Summary: We propose an efficient method for solving the time-dependent Kohn-Sham equations in free space using the Fourier contour deformation (FCD) approach. FCD allows for high-order accurate numerical solutions without the need for artificial boundary conditions, making it a valuable tool for simulations in molecular complexes.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2023)
Article
Chemistry, Physical
Carlos Manuel de Armas-Morejon, Luis A. Montero-Cabrera, Angel Rubio, Joaquim Jornet-Somoza
Summary: This study proposes a machine learning approach to model the absorption spectra of organic molecules. By using low-cost density functional theory methods and neural networks, the electronic descriptors can accurately predict the density and absorption spectra of electronic excited states, achieving results close to chemical accuracy.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2023)
Article
Chemistry, Physical
Torsha Moitra, Lukas Konecny, Marius Kadek, Angel Rubio, Michal Repisky
Summary: This article proposes a methodology for simulating attosecond pump-probe transient absorption spectroscopy (TAS) using relativistic real-time, time-dependent density functional theory (RT-TDDFT). It includes the treatment of relativistic effects and both the valence and core energy regimes. By introducing the atomic mean-field exact two-component (amfX2C) Hamiltonian, computational cost is reduced while preserving the accuracy of the parent 4c method. The methodology is applied to study valence and near-L2,3-edge TAS processes of experimentally relevant systems and provides additional physical insights using relativistic nonequilibrium response theory.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Max Rossmannek, Fabijan Pavosevic, Angel Rubio, Ivano Tavernelli
Summary: Quantum computing is a promising platform for simulating strongly correlated systems in chemistry. However, due to hardware limitations, its application is currently limited to small chemical systems. The quantum embedding approach, particularly the projection-based embedding method, is employed in this study to combine the variational quantum eigensolver (VQE) algorithm with density functional theory (DFT). The developed VQE-in-DFT method is implemented efficiently on a real quantum device and used to simulate the triple bond breaking process in butyronitrile. The results demonstrate the potential of this method for simulating systems with strongly correlated fragments on a quantum computer.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Ofer Neufeld, Nicolas Tancogne-Dejean, Umberto De Giovannini, Hannes Huebener, Angel Rubio
Summary: Irradiating solids with ultrashort laser pulses can induce femtosecond timescale magnetization dynamics. In this study, we predict that nonmagnetic materials can transiently transform into magnetic ones through extremely nonlinear spin-flipping processes on the attosecond timescale. We also show that even under linearly polarized driving, the magnetization of the system transiently oscillates due to transverse light-driven currents in the solid.
NPJ COMPUTATIONAL MATERIALS
(2023)
Review
Chemistry, Multidisciplinary
Michael Ruggenthaler, Dominik Sidler, Angel Rubio
Summary: This review presents the theoretical foundations and first-principles frameworks to describe quantum matter within quantum electrodynamics (QED) in the low-energy regime, with a focus on polaritonic chemistry. Starting from fundamental physical and mathematical principles, the review explores the ab initio nonrelativistic QED and its applications in approximative computational methods. The benefits of these methods in understanding photon-induced changes of chemical properties and reactions are highlighted, and open theoretical questions in polaritonic chemistry are identified.
Article
Chemistry, Physical
Thomas Schnappinger, Dominik Sidler, Michael Ruggenthaler, Angel Rubio, Markus Kowalewski
Summary: Experimental studies have shown that optical cavities can influence chemical reactions through strong coupling between vibrational or electronic modes and quantized cavity modes. However, the understanding of the interaction between molecules and confined light modes is currently incomplete. In this study, we present a theoretical model that considers intermolecular interactions and accurately describes strongly coupled molecular ensembles with an optical cavity. Our results demonstrate the importance of cavity-mediated dipole-dipole interactions in energetic changes of individual molecules in the coupled ensemble.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Ofer Neufeld, Hannes Huebener, Gregor Jotzu, Umberto De Giovannini, Angel Rubio
Summary: We study the effects of low-frequency linearly polarized laser-dressing on materials with valley and topological properties. We find that the laser can move the Dirac and Weyl nodes, as well as the valley minima, by exploiting the band nonlinearity. This effect has wide applicability and can be used to tailor material properties. Our results highlight the importance of the full band structure in understanding nonlinear optical phenomena in solids.
Article
Chemistry, Physical
Weijie Li, Zach Hadjri, Luka M. Devenica, Jin Zhang, Song Liu, James Hone, Kenji Watanabe, Takashi Taniguchi, Angel Rubio, Ajit Srivastava
Summary: By using a WS2/WSe2/WS2 heterotrilayer, this study creates a quantum superposition of quadrupolar excitons and reveals the mechanism of this phase transition under different electric field conditions. The results demonstrate that van der Waals heterotrilayers can be used to engineer light-matter interactions and explore quantum phase transitions between many-exciton phases.
Article
Physics, Multidisciplinary
Angana Mondal, Ofer Neufeld, Zhong Yin, Zahra Nourbakhsh, Vit Svoboda, Angel Rubio, Nicolas Tancogne-Dejean, Hans Jakob Worner
Summary: The study demonstrates that high-harmonic spectroscopy can be applied to liquid samples and that the cut-off energy is a characteristic property of the liquid. This technique can also determine the effective mean free paths of electrons in liquids.
Article
Physics, Multidisciplinary
Ofer Neufeld, Nicolas Tancogne-Dejean, Hannes Huebener, Umberto De Giovannini, Angel Rubio
Summary: This study presents a fully ab initio investigation of high harmonic generation (HHG) from two-dimensional topological insulators. The analysis of spectra and previously proposed topological signatures suggests that none of the observables proposed thus far is a reliable indicator of material topology. This highlights the need for caution when interpreting HHG spectra for topological signatures.
Article
Physics, Multidisciplinary
Lukas Weber, Emil Vinas Bostroem, Martin Claassen, Angel Rubio, Dante M. Kennes
Summary: Strong light-matter interactions in an optical cavity can control the properties of condensed matter systems. In this study, Quantum Monte Carlo simulations are used to investigate the scaling behavior of a 2D quantum critical magnet coupled to a single cavity mode. The results show that while the critical point remains unchanged, the critical fluctuations are significantly enhanced and deviate from the expected scaling exponent based on perturbation theory.
COMMUNICATIONS PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Nicolas Tancogne-Dejean, Angel Rubio, Carsten A. Ullrich
Summary: We propose a semilocal exchange-correlation energy functional for noncollinear spin density functional theory, based on short-range expansions of the spin-resolved exchange hole and the two-body density matrix. Our functional is explicitly derived for noncollinear magnetism, is U(1) and SU(2) gauge invariant, and produces nonvanishing exchange-correlation torques. Testing the functional on frustrated antiferromagnetic chromium clusters, the exchange part shows favorable performance compared to the more expensive Slater and optimized effective potentials, revealing a delicate interplay between exchange and correlation torques.