Article
Nanoscience & Nanotechnology
Xin He, Chenhui Zhang, Dongxing Zheng, Peng Li, John Q. Xiao, Xixiang Zhang
Summary: With the recent advancements in two-dimensional ferromagnets, it is now feasible to develop high-quality all-2D spintronic devices. In this study, nonlocal spin valves were successfully fabricated using Fe3GeTe2 as the spin source and detector and multilayer graphene as the spin transport channel. The spin transport signal strongly depended on temperature and vanished below the Curie temperature of the Fe3GeTe2 flakes. Our results suggest potential applications of van der Waals heterostructures in spintronic devices.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Materials Science, Multidisciplinary
Kazutoshi Miwa
Summary: This paper presents the linear-response approach using the nonlocal van der Waals density functionals, considering three types of perturbations: atomic displacements, uniform electric fields, and strain. Formulas for calculating the response to strain are derived for both the van der Waals density functionals and the generalized gradient approximation. The linear-response method is implemented within the ultrasoft pseudopotential scheme. The method is applied to weakly coupled layered materials, such as graphite and MoS2, and the results confirm the validity of the derived formulas and demonstrate the utility of the linear-response method for weakly coupled van der Waals systems.
Review
Chemistry, Inorganic & Nuclear
Wei Zheng, Xianghong Liu, Jiayue Xie, Guocai Lu, Jun Zhang
Summary: The article provides a comprehensive overview of the design and application of vdW junctions based on W and Mo-TMDs materials for gas sensors, discussing methods for constructing different forms of vdW heterojunctions and summarizing the latest advances and future challenges in their application in chemical gas sensors.
COORDINATION CHEMISTRY REVIEWS
(2021)
Review
Chemistry, Multidisciplinary
Xiangdong Guo, Wei Lyu, Tinghan Chen, Yang Luo, Chenchen Wu, Bei Yang, Zhipei Sun, F. Javier Garcia de Abajo, Xiaoxia Yang, Qing Dai
Summary: 2D monolayers can be vertically stacked in van der Waals heterostructures to support a wide range of confined polaritons. This offers advantages in terms of controlling the constituent layers, stacking sequence, and twist angles. These heterostructures have extended the performance and functions of polaritons, and potential applications include nanophotonic integrated circuits.
ADVANCED MATERIALS
(2023)
Article
Physics, Multidisciplinary
Flavia Pennini, Angel Plastino
Summary: We undertake a van der Waals inquiry at very low temperatures and explore its relationship with the van der Waals gas-liquid transition. By using novel thermal statistical quantifiers, we gain fruitful insights.
Article
Multidisciplinary Sciences
A. J. Sternbach, S. H. Chae, S. Latini, A. A. Rikhter, Y. Shao, B. Li, D. Rhodes, B. Kim, P. J. Schuck, X. Xu, X-Y Zhu, R. D. Averitt, J. Hone, M. M. Fogler, A. Rubio, D. N. Basov
Summary: Layered crystals, such as tungsten diselenide, can exhibit unconventional optical properties that allow for the propagation of subdiffractional waveguide modes with hyperbolic dispersion. This study demonstrates optically induced hyperbolicity in WSe2 and explores the role of quantum transitions of excitons in the observed polaritonic response.
Article
Nanoscience & Nanotechnology
Yue Zhao, Gang Wu, Kuan-Ming Hung, Jiung Cho, Miri Choi, Cormac O. Coileain, Georg S. Duesberg, Xiang-Kui Ren, Ching-Ray Chang, Han-Chun Wu
Summary: In this work, we fabricated field effect transistor gas sensors based on mechanically exfoliated van der Waals (vdW) layered materials and investigated their electrical field-dependent gas sensing properties. The results showed good agreement between experimental and theoretical values, indicating the validity of the Langmuir absorption model for vdW materials. Additionally, we demonstrated that the device sensing behavior strongly depends on carrier availability, leading to giant sensitivities and strong selectivity at the sensitivity singularity. Furthermore, our study revealed that these features can be utilized to quickly detect and differentiate low concentrations of mixed hazardous gases using sensor arrays.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Review
Chemistry, Multidisciplinary
Hui-Lei Hou, Cosimo Anichini, Paolo Samori, Alejandro Criado, Maurizio Prato
Summary: In the past 15 years, 2D materials have revolutionized materials science and become powerful components for high-performance chemical sensors. By forming van der Waals heterostructures (VDWHs), the individual drawbacks of 2D materials can be overcome, leading to superior sensitivities, selectivity, and stability. This review discusses the latest developments in chemical sensors based on VDWHs of 2D materials, including sensing mechanisms and future directions with potential impact in environmental sciences and biomedical applications.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Review
Chemistry, Multidisciplinary
Fang Wang, Tao Zhang, Runzhang Xie, Anna Liu, Fuxing Dai, Yue Chen, Tengfei Xu, Hailu Wang, Zhen Wang, Lei Liao, Jianlu Wang, Peng Zhou, Weida Hu
Summary: With the continuous advancement of nanofabrication techniques and the discovery of useful manipulation mechanisms in high-performance applications, the morphology and usage of junction devices in photodetectors have undergone fundamental revolution. New types of photodetectors, not relying on any junction, have emerged, offering high signal-to-noise ratio and multidimensional modulation. This review focuses on a unique category of material systems, van der Waals materials, which support novel high-performance photodetectors beyond junctions.
ADVANCED MATERIALS
(2023)
Article
Multidisciplinary Sciences
Long Zhang, Fengcheng Wu, Shaocong Hou, Zhe Zhang, Yu-Hsun Chou, Kenji Watanabe, Takashi Taniguchi, Stephen R. Forrest, Hui Deng
Summary: Controlling matter-light interactions with cavities is crucial in modern science and technology. By integrating MoSe2-WS2 heterobilayers in a microcavity, cooperative coupling between moire-lattice excitons and microcavity photons has been established, providing versatile control of both matter and light. This moire polariton system combines strong nonlinearity and microscopic-scale tuning of matter excitations, offering a platform to study collective phenomena from tunable arrays of quantum emitters.
Review
Chemistry, Multidisciplinary
Tianping Ying, Tongxu Yu, Yanpeng Qi, Xiaolong Chen, Hideo Hosono
Summary: By breaking traditional alloying strategy restrictions, the high entropy concept has expanded the field of alloy exploitation. This review focuses on the combination of the high entropy concept and van der Waals systems to create a new category of materials called high entropy van der Waals materials (HEX). The design strategy for HEX incorporates the local features of high entropy materials and the holistic degrees of freedom in van der Waals materials, successfully leading to the discovery of various high entropy compounds with desirable physical properties. Additionally, deliberate design of structural units and their stacking configuration in HEX can also enhance catalytic performance.
Article
Chemistry, Multidisciplinary
Xiaoqing Chen, Yu Zhang, Ruijuan Tian, Xianghu Wu, Zhengdong Luo, Yan Liu, Xinran Wang, Jianlin Zhao, Xuetao Gan
Summary: A quadratically nonlinear photodetector (QNPD) composed of a van der Waals (vdW) stacked GaSe/InSe heterostructure is reported in this study. The QNPD exhibits unique electronic and optical attributes and extends the photodetection wavelength range from 900 to 1750 nm due to the extra second-harmonic generation (SHG) process in GaSe/InSe. It is highly sensitive to the variation of optical intensity and can be used as an autocorrelator for measuring ultrafast pulse widths and an optoelectronic mixer for signal processing.
Review
Materials Science, Multidisciplinary
Lixin Liu, Tianyou Zhai
Summary: The article reviews the latest research activities on wafer-scale vdWHs and their applications, outlining preparation strategies and applications to showcase their potential in electronic, optoelectronic, and flexible devices fields.
Article
Chemistry, Multidisciplinary
Maurits J. A. Houmes, Samuel Manas-Valero, Alvaro Bermejillo-Seco, Eugenio Coronado, Peter G. Steeneken, Herre S. J. van der Zant
Summary: This article investigates the structural anisotropy of CrPS4 and its relationship with magnetic phase transitions and discovers different mechanical response behavior compared to previously studied van der Waals magnets. The results demonstrate the potential of CrPS4 in the field of low-dimensional magnetism and show the potential of mechanical resonators in studying structural modifications in 2D materials and van der Waals heterostructures.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Haonan Ling, Jacob B. Khurgin, Artur R. Davoyan
Summary: Layered van der Waals materials provide unique atomic-void channels with subnanometer dimensions, offering opportunities for advanced applications such as sensing and quantum information. Theoretical limits of light guiding in these channels show that materials with strong resonances, excitonic and polaritonic properties are ideal for deeply subwavelength light guiding. Transition metal dichalcogenides with excitonic properties can concentrate over 70% of optical power within them.
Article
Chemistry, Physical
Pedro Borlido, Jonathan Schmidt, Ahmad W. Huran, Fabien Tran, Miguel A. L. Marques, Silvana Botti
NPJ COMPUTATIONAL MATERIALS
(2020)
Article
Computer Science, Interdisciplinary Applications
Oleg Rubel, Fabien Tran, Xavier Rocquefelte, Peter Blaha
Summary: A degenerate perturbation k . p approach for effective mass calculations is implemented in WIEN2k using all-electron DFT. The accuracy is tested on major group IVA, IIIA-VA, and IIB-VIA semiconductor materials. Effective mass calculations in graphene and CuI with defects are presented as illustrative applications, with additional local orbitals needed for states with significant Cu-d character. Caveats related to differences between velocity and momentum matrix elements are discussed in the context of non-local potentials application.
COMPUTER PHYSICS COMMUNICATIONS
(2021)
Article
Chemistry, Physical
Abhilash Patra, Subrata Jana, Prasanjit Samal, Fabien Tran, Leila Kalantari, Jan Doumont, Peter Blaha
Summary: This study evaluates the accuracy of recently developed semilocal exchange-correlation energy functionals and potentials in predicting the band gap of 2D materials, comparing their performance against each other. The results show that different methods have their own characteristics in calculating band gaps of 2D materials, with GLLB-SC method being more accurate in certain cases.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Physical
Augustin Bussy, Jurg Hutter
Summary: It is found that LR-TDDFT for core level spectroscopy using standard local functionals suffers from errors, and a correction scheme based on many-body perturbation theory is proposed. The correction scheme takes into account self-interaction error and orbital relaxation, improving computational efficiency and yielding corrected spectra in a single calculation.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Fabien Tran, Jan Doumont, Leila Kalantari, Peter Blaha, Tomas Rauch, Pedro Borlido, Silvana Botti, Miguel A. L. Marques, Abhilash Patra, Subrata Jana, Prasanjit Samal
Summary: In this study, various DFT approximations were evaluated for their accuracy in predicting bandgaps of two-dimensional materials. The GLLB-SC potential and mTASK functional were found to provide bandgaps closest to G(0)W(0). The MBJ potential showed good accuracy comparable to the more expensive HSE06 functional.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Frederick Stein, Juerg Hutter
Summary: Double-hybrid density functionals are an important method for molecular electronic-structure calculations, but their wide applicability for periodic systems is hindered by high computational costs and the lack of efficient gradient implementation in the condensed phase. In this study, we present an efficient and accurate methodology to tackle condensed phase systems by implementing forces and stress tensors for double-hybrid density functionals within the Gaussian and plane-waves electronic structure framework. The efficiency of the implementation is demonstrated through applications to water systems and molecular crystals.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Peter Kovacs, Fabien Tran, Allan Hanbury, Georg K. H. Madsen
Summary: Benchmarking DFT functionals can be complex due to the dependence of results on properties and materials used. A clustering approach based on density gradient and kinetic energy density distribution can identify chemically distinct solids. The proposed method aims to create smaller or rebalanced data sets to accurately replicate average errors of the original set, which can be applied to make general benchmarks or train new functionals.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Chemistry, Physical
Peter Kovacs, Fabien Tran, Peter Blaha, Georg K. H. Madsen
Summary: This study systematically explores the space of generalized gradient approximation (GGA) and meta-GGA (mGGA) exchange approximations by training new functionals, aiming to improve accurate predictions of lattice parameter, cohesive energy, and bandgap. The trained functionals perform similarly to specialized functionals for bandgap predictions and outperform them for the other two properties.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Arghya Ghosh, Subrata Jana, Manish K. Niranjan, Fabien Tran, David Wimberger, Peter Blaha, Lucian A. Constantin, Prasanjit Samal
Summary: This study demonstrates that the use of the MGGAC method can accurately calculate the ground-state phase of MnO, consistent with results from high-level correlation methods. Additionally, the use of hybrid functionals (including Hartree-Fock exchange) can also yield the correct ground-state phase. These methods have the advantage of being computationally inexpensive when calculating the relative stability of antiferromagnetic transition-metal oxides.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Augustin Bussy, Ole Schutt, Jurg Hutter
Summary: The development of novel double-hybrid density functionals has led to higher levels of accuracy and insights into matter's fundamental properties. Low-scaling methods for Hartree-Fock exchange, SOS-MP2, and direct RPA energy gradients have been developed and implemented in the CP2K software package, enabling their application to large and periodic systems.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Fabian Belleflamme, Anna-Sophia Hehn, Marcella Iannuzzi, Juerg Hutter
Summary: Accurate descriptions of intermolecular interactions are crucial for molecular liquid simulations. To achieve both accuracy and computational efficiency, we propose an electronic structure method that combines the Harris functional approach with approximately linear-scaling density functional theory (DFT). By constructing a Lagrangian energy functional, the non-variational nature of the Harris functional is addressed. The method allows for simulations with accuracies close to the Kohn-Sham DFT reference, making it suitable for ab initio molecular dynamics simulations of large molecular systems.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Jan Doumont, Fabien Tran, Peter Blaha
Summary: This article introduces the self-consistent implementation of MGGA functionals in augmented plane wave methods, discussing technical aspects and validating the implementation by calculating properties such as band gaps, lattice constants, and magnetic moments, as well as the electric field gradient on transition-metal atoms.
Article
Mathematics, Interdisciplinary Applications
Leila Kalantari, Fabien Tran, Peter Blaha
Summary: Experimental studies have shown the possible production of hydrogen through photocatalytic water splitting using metal oxide nanoparticles attached to an anatase TiO2 surface. In this work, density functional theory (DFT) calculations were conducted to provide a detailed description of the stability and geometry of metal oxide clusters on the TiO2 surface. The results indicate that Ni clusters have higher formation energy, and the adsorption energy of Ni increases with cluster size.
Article
Materials Science, Multidisciplinary
Leila Kalantari, Fabien Tran, Peter Blaha
Summary: This study introduces a method using a local function for estimating interatomic correlation to determine the necessity of applying a Hubbard U on-site correction in the DFT+U method. This is particularly important for analyzing atomic correlations in scenarios such as interfaces and oxygen-covered metal surfaces.
Article
Materials Science, Multidisciplinary
Fabien Tran, Guillaume Baudesson, Jess Carrete, Georg K. H. Madsen, Peter Blaha, Karlheinz Schwarz, David J. Singh
