Article
Chemistry, Physical
Jared R. Williams, Nicolas Tancogne-Dejean, Carsten A. Ullrich
Summary: Time-dependent density-functional theory (TDDFT) is an efficient method for calculating optical spectra, providing insight into exciton dynamics by obtaining exciton wave functions and understanding the formation and dissociation of excitons in real time.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2021)
Article
Physics, Condensed Matter
Daniel Vieira
Summary: The emergence of Wigner oscillations is obtained by employing a time-dependent density-functional theory formalism to simulate a real time cooling process in one-dimensional quantum dots.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Materials Science, Multidisciplinary
Yi Li, Zhen Feng, Qian Sun, Yaqiang Ma, Yanan Tang, Xianqi Dai
Summary: The MoSe2/BAs van der Waals heterostructures exhibit excellent stability and optical properties. Their band structure can be modulated by in-plane strains and external electric fields, making them suitable for thermoelectric and photovoltaic applications.
RESULTS IN PHYSICS
(2021)
Article
Chemistry, Physical
Fanshi Wu, Junjie Yuan, Wenxin Lai, Liangwei Fu, Biao Xu
Summary: This study demonstrates a convenient approach to synthesize layered materials with isotropic electrical and thermal transport behaviors through a precursor of metastable phase. The effect of Ag doping on facilitating the formation of metastable SnS and the intrinsic mechanisms of its nearly isotropic thermoelectric properties are elucidated.
Article
Physics, Condensed Matter
John McFarland, Efstratios Manousakis
Summary: Imaginary-time time-dependent density functional theory (it-TDDFT) is proposed as an alternative method for obtaining the ground state within density functional theory, avoiding convergence difficulties encountered by the self-consistent-field iterative method. By modifying the Quantum ESPRESSO package, it-TDDFT propagation for periodic systems has been successfully implemented, demonstrating accurate results for different calculations using ultra-soft or norm-conserving pseudo potentials.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Review
Chemistry, Physical
Neepa T. Maitra
Summary: Time-dependent density functional theory is a preferred method for calculating spectra and response properties in physics, chemistry, and biology. Its ability to scale to larger systems has made computations possible that were not previously achievable. While simple functional approximations have been successful in handling increasingly complex and interesting systems, there is a growing awareness that these approximations may fail for certain classes of problems. This review discusses the challenges and progress in describing double excitations and charge-transfer excitations, two common obstacles to the theory's application.
ANNUAL REVIEW OF PHYSICAL CHEMISTRY
(2022)
Article
Multidisciplinary Sciences
John P. Perdew, Adrienn Ruzsinszky, Jianwei Sun, Niraj K. Nepal, Aaron D. Kaplan
Summary: Strong correlations within a symmetry-unbroken ground-state wavefunction may manifest in approximate density functional theory as symmetry-broken spin densities or total densities, arising from soft modes of fluctuations such as spin-density or charge-density waves. An approximate density functional that breaks symmetry can be more revealing than an exact functional that does not, with examples including the stretched H-2 molecule, antiferromagnetic solids, and the static charge-density wave/Wigner crystal phase of a low-density jellium. Time-dependent density functional theory quantitatively shows that the static charge-density wave is a soft plasmon, with the frequency of a related density fluctuation dropping to zero.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Biochemistry & Molecular Biology
Austin Biaggne, William B. Knowlton, Bernard Yurke, Jeunghoon Lee, Lan Li
Summary: The properties of dye monomers greatly influence their aggregation ability and exciton dynamics. By engineering dyes with specific substituents, optimal key properties like hydrophobicity and dipole moments can be achieved. This study found that electron withdrawing substituents significantly affect the solvation energy of the dye, while various pairs of substituents can enhance the static dipole difference.
Article
Chemistry, Physical
Al Rey Villagracia, Hui Lin Ong, Dhan Shemaiah Bayasen, Hsin Lin, Melanie David, Nelson Arboleda
Summary: The study introduced impurities such as calcium, potassium, and magnesium into planar aluminene, finding that these interstitial dopants can affect hydrogen adsorption behavior, enhancing hydrogen storage performance. This chemisorption was validated by density functional theory, demonstrating the potential of these materials for hydrogen storage.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Engineering, Environmental
Sharma S. R. K. C. Yamijala, Ravindra Shinde, Kota Hanasaki, Zulfikhar A. Ali, Bryan M. Wong
Summary: PFASs are hazardous contaminants found in drinking water sources, and recent experimental efforts have focused on photo-induced processes to accelerate their degradation. This study provides crucial insights into the mechanism of photo-induced degradation of PFASs using RT-TDDFT calculations, showing that photo-induced excitations can be highly selective in dissociating the C-F bond.
JOURNAL OF HAZARDOUS MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Tetsuro Habe, Koichi Nakamura
Summary: The research reveals the presence of excitons in the monolayer crystal and evaluates its optical property using numerical methods. Additionally, it confirms the consistency of the optical property of the bulk crystal with previous experimental results, independent of the number of layers.
Article
Chemistry, Physical
Lukas Schreder, Sandra Luber
Summary: The study introduces a method for obtaining local electric dipole moments, which can be applied in modern polarization theory and is suitable for molecular dynamics and time-dependent DFT. This method can help analyze absorption and infrared spectra by decomposing them into localized subsystem contributions.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
F. Aryasetiawan
Summary: It is found that the equation of motion for the one-particle Green function in an interacting many-electron system is determined by a time-dependent exchange-correlation potential, which is the Coulomb potential of a time-varying exchange-correlation hole. This exchange-correlation hole satisfies a sum rule, extending the well-known sum rule of the static exchange-correlation hole. It is suggested that this proposed formalism may offer an alternative approach for calculating the Green function by approximating the exchange-correlation hole or potential using techniques such as the local-density approximation.
Article
Chemistry, Physical
Yevhen Horbatenko, Saima Sadiq, Seunghoon Lee, Michael Filatov, Cheol Ho Choi
Summary: The MRSF-TDDFT method demonstrates high accuracy in describing the multiconfigurational electronic states of diradicals and diradicaloids, avoiding spin-contamination pitfalls. It accurately predicts adiabatic singlet-triplet gaps and various effects in different systems.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2021)
Article
Chemistry, Multidisciplinary
Lulu Huang, Yuanyue Li, Shengmao Sha, Bangzhi Ge, Yucheng Wu, Jian Yan, Yuan Kong, Jian Zhang
Summary: Defect engineering is an effective method to suppress lattice thermal conductivity. By designing multiple microstructural defects, such as vacancies, holes, nano precipitates, dislocations, and strain, in Cu1-xAgxGaTe2 solid solutions, the thermal conductivity is significantly reduced, leading to record-breaking thermoelectric performance.
Article
Chemistry, Multidisciplinary
Longji Cui, Yunxuan Zhu, Peter Nordlander, Massimiliano Di Ventra, Douglas Natelson
Summary: By using plasmonic tunnel junctions as a platform, a much greater plasmonic light emission can be achieved under combined electrooptical excitation. The observed spectra suggest interactions of plasmon-induced hot carriers and electronic anti-Stokes Raman scattering as possible mechanisms for the enhanced emission.
Article
Mathematics, Applied
Yuan-Hang Zhang, Massimiliano Di Ventra
Summary: Digital memcomputing machines are a novel type of machines designed to solve combinatorial optimization problems, with solutions reported to have substantial advantages over current solvers. Even in the presence of numerical noise, solutions can still be achieved, with the forward Euler method being the most efficient. Adding to this, there is a solvable-unsolvable transition in the system at a critical threshold, showing the robustness and usefulness of DMMs in solving complex optimization problems.
Article
Neurosciences
Nan Du, Xianyue Zhao, Ziang Chen, Bhaskar Choubey, Massimiliano Di Ventra, Ilona Skorupa, Danilo Buerger, Heidemarie Schmidt
Summary: BiFeO3(BFO) artificial synapses exhibit various long-term plasticity functions depending on time, cycles, and frequency, with their learning windows capable of wide time scale configurability based on applied waveforms. In addition, a study on generalized frequency-dependent plasticity reveals that modulation of pulse width and pulse interval time within one spike cycle can lead to both synaptic potentiation and depression effects.
FRONTIERS IN NEUROSCIENCE
(2021)
Article
Physics, Applied
Pieter Gypens, Bartel Van Waeyenberge, Massimiliano Di Ventra, Jonathan Leliaert, Daniele Pinna
Summary: The end of Moore's law has led to the exploration of low-power computing alternatives, with nanomagnetic logic being a promising approach. However, nanomagnetic logic faces limitations in solving certain problems efficiently. Researchers have introduced nanomagnetic self-organizing logic gates that enable reversible computing, with the ability to solve complex problems like factorization through numerical modeling. This approach opens up new possibilities for exploring memcomputing, a non-traditional computing paradigm.
PHYSICAL REVIEW APPLIED
(2021)
Article
Engineering, Electrical & Electronic
Ziang Chen, Nan Du, Mahdi Kiani, Xianyue Zhao, Ilona Skorupa, Stefan E. Schulz, Danilo Buerger, Massimiliano Di Ventra, Ilia Polian, Heidemarie Schmidt
Summary: In this research, a high-security level hardware primitive system is developed using a novel electroforming-free analog memristive device. The system utilizes the power conversion efficiency generated at different resistance states of the memristor, achieving a significant frequency enhancement by studying the influence of input voltage sources. The encoded data from the physically implemented system shows high randomness distribution and security level through various statistical tests.
IEEE TRANSACTIONS ON NANOTECHNOLOGY
(2022)
Article
Multidisciplinary Sciences
Girish Sharma, Indra Yudhistira, Nilotpal Chakraborty, Derek Y. H. Ho, M. M. Al Ezzi, Michael S. Fuhrer, Giovanni Vignale, Shaffique Adam
Summary: The theory of phonon-dominated transport in twisted bilayer graphene explains experimental observations and contrasts with the Planckian dissipation mechanism, shedding light on the mechanisms responsible for the strongly correlated insulating and superconducting phases. Accurate treatment of electron-phonon scattering beyond the usual methods provides insights and concrete predictions for ongoing experiments.
NATURE COMMUNICATIONS
(2021)
Article
Physics, Applied
Ariel Norambuena, Felipe Torres, Massimiliano Di Ventra, Raul Coto
Summary: The article introduces a polariton-based quantum memristor, where the memristive nature is controlled by a time-varying atom-cavity detuning. The dynamical hysteresis and plasticity of the quantum memristor make it versatile for various applications.
PHYSICAL REVIEW APPLIED
(2022)
Article
Physics, Multidisciplinary
Yan Ru Pei, Massimiliano Di Ventra
Summary: Spin glasses are difficult to study due to their non-convex landscapes, but a new non-equilibrium approach using classical dynamics with memory allows for efficient exploration of their low-temperature phases.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2022)
Article
Physics, Multidisciplinary
Massimiliano Di Ventra, Yuriy Pershin, Chih-Chun Chien
Summary: This article presents the discovery of a custodial symmetry in a classical electrical circuit with memory and explores the interplay between symmetry and memory. The topology edge state in the circuit is still protected by the custodial chiral symmetry, despite the explicit breaking of chiral symmetry caused by memory. These predictions can be verified experimentally.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Applied
Riccardo Tomasello, Roman Verba, Victor Lopez-Dominguez, Francesca Garesci, Mario Carpentieri, Massimiliano Di Ventra, Pedram Khalili Amiri, Giovanni Finocchio
Summary: We theoretically demonstrate that voltage-controlled magnetic anisotropy (VCMA) can excite linear and parametric resonant modes in easy-axis antiferromagnets (AFMs), and it is more efficient than other methods. This has important implications for the efficient electrical control of the Neel vector and the detection of high-frequency dynamics.
PHYSICAL REVIEW APPLIED
(2022)
Article
Nanoscience & Nanotechnology
Yuriy V. Pershin, Jinsun Kim, Timir Datta, Massimiliano Di Ventra
Summary: This study validates a recent test method and applies it to a device claimed to be a memristor. The results demonstrate that the device is actually an inductor with memory, not a memristor. This finding raises doubts about the existence and easy creation of ideal memristors.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2022)
Article
Chemistry, Physical
Nicolas Tancogne-Dejean, Florian G. Eich, Angel Rubio
Summary: In this work, the authors used first-principles simulations to study high-harmonic generation in the topological Diract semimetal Na3Bi and analyzed the effect of spin-orbit coupling on the harmonic response. They found that spin-orbit coupling affects the excitation of carriers, modifies the electron velocity in each spin channel, and changes the timing of emitted harmonics. Furthermore, they discovered that spin-orbit coupling directly couples the charge current to the spin currents, suggesting potential applications in high-harmonic spectroscopy of spin currents in solids.
NPJ COMPUTATIONAL MATERIALS
(2022)
Proceedings Paper
Engineering, Electrical & Electronic
Massimiliano Di Ventra
Summary: Quantum computing utilizes quantum phenomena for information processing and is considered the future of computing, but faces challenges in practical realization. MemComputing, on the other hand, employs non-quantum dynamical systems and time non-locality for computation, making it efficient to emulate in software and easier to transition to hardware.
2022 IEEE 22ND INTERNATIONAL CONFERENCE ON NANOTECHNOLOGY (NANO)
(2022)
Article
Optics
Yuan -Hang Zhang, Massimiliano Di Ventra
Summary: This study proposes a training method that utilizes the modes of the neural network distribution to provide global information, significantly improving the quality of reconstructed quantum states. This method is applicable to other types of neural networks and has the potential to efficiently tackle previously unmanageable problems.
Article
Materials Science, Multidisciplinary
S. De Palo, P. E. Trevisanutto, G. Senatore, G. Vignale
Summary: The study uses quantum continuum mechanics to calculate the excitation spectrum of a coupled electron-hole bilayer, indicating a discontinuity in the chemical potential of electrons and holes when their numbers are equal. The system exhibits incompressibility, with the presence of electron-hole correlation causing a unique feature in the static density-density response function.