Article
Multidisciplinary Sciences
Jacqueline Bloch, Andrea Cavalleri, Victor Galitski, Mohammad Hafezi, Angel Rubio
Summary: A goal of modern condensed-matter physics is to search for states of matter with emergent properties and desirable functionalities. By controlling light-matter interactions, it is possible to manipulate and synthesize strongly correlated quantum matter, leading to phenomena like photon-mediated superconductivity, cavity fractional quantum Hall physics, and optically driven topological phenomena.
Article
Chemistry, Physical
Haodong Zhang, Jingxiang Zou, Xiaochuan Ren, Shuhua Li
Summary: The Anequation-of-motion block-correlated coupled cluster method based on the generalized valence bond wave function (EOM-GVB-BCCC) is proposed to describe low-lying excited states for strongly correlated systems. The EOM-GVB-BCCC2b method, which includes up to two-pair correlation, has been successfully implemented and tested for several strongly correlated systems. The results of EOM-GVB-BCCC2b for a water hexamer and four conjugated diradical species are consistent with the density matrix renormalization group (DMRG) results.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Review
Chemistry, Multidisciplinary
Roman Kuzian
Summary: The discovery of high-Tc superconductivity in cuprates in 1986 shifted the focus of solid-state research to strongly correlated transition metal compounds, which had previously been considered exotic worlds only of interest to pure theorists. Condensed matter physics topics such as high-Tc superconductivity, colossal magnetoresistance, multiferroicity, and ferromagnetism in diluted magnetic semiconductors are often related to these strongly correlated systems. The study of these compounds requires methods and models beyond the mean field approximation, and examples of response function calculations are discussed for the interpretation of experimental information.
Article
Chemistry, Physical
Bei-Lei Liu, Yue-Chao Wang, Yu Liu, Hai-Feng Liu, Hai-Feng Song
Summary: We have developed a doubly screened Coulomb correction (DSCC) method for efficiently correcting the on-site Coulomb interaction in strongly correlated materials, and it can accurately simulate electronic and magnetic properties. Compared to hybrid functionals, DSCC has comparable accuracy but is an order of magnitude faster, and it can reflect the difference in the Coulomb interaction between metallic and insulating situations.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Pavlo Golub, Andrej Antalik, Pavel Beran, Jiri Brabec
Summary: We have developed a new machine-learning model to predict mutual information for strongly correlated systems, which is a complex quantity but carries important information about the correlation structure. In this study, we replaced expensive DMRG calculations with our newly trained ML model to predict mutual information. We demonstrated the model's performance in determining correlation structure and orbital ordering for accurate DMRG calculations, comparing the results with those obtained from accurate DMRG calculations.
CHEMICAL PHYSICS LETTERS
(2023)
Review
Multidisciplinary Sciences
Vasily R. Shaginyan, Alfred Z. Msezane, Mikhail V. Zverev
Summary: This short review discusses the transport properties of strongly correlated Fermi systems, such as heavy fermion metals and high-Tc superconductors. Their transport properties, influenced by strong inter-particle interactions, exhibit unconventional behavior such as temperature-linear resistivity and non-Fermi liquid behavior.
Article
Optics
Ting Zhang, Neil Qiang Su
Summary: In this study, the hypercomplex Kohn-Sham (HCKS) formalism is explored and a new exact functional theory called 1-HCKS is developed as an alternative to traditional Kohn-Sham density functional theory (KS-DFT) and reduced density matrix functional theory (RDMFT) for dealing with strongly correlated systems. The unique feature of 1-HCKS is the introduction of hierarchical correlation orbitals that can capture strong correlation with fractional occupations, providing a balance between the rigidity of KS-DFT and flexibility of RDMFT. This approach eliminates the convergence and basis set dependence issues encountered in RDMFT.
Review
Astronomy & Astrophysics
Julio Marny Hoff da Silva, Gabriel Marcondes Caires da Rocha
Summary: This paper revisits the fundamental notion of continuity in representation theory, focusing particularly on its applications in the study of quantum physics. After studying the main theorem in representation theory, the significant aspect of continuity in the analytic foundations of Wigner's work is highlighted. The paper concludes by reviewing the connection between continuity, the possibility of defining certain local groups, and their relation to projective representations.
Article
Materials Science, Multidisciplinary
Yu. S. Orlov, S. V. Nikolaev, V. A. Dudnikov, S. G. Ovchinnikov
Summary: The magnetic structure and exciton condensate formation of local magnetic excitons in strongly correlated systems near the spin crossover under high pressure were considered using an effective Hamiltonian obtained from a two-band Hubbard model. The coexistence of long-range antiferromagnetic order and exciton condensate, as well as the magnetization caused by the condensation of local magnetic excitons, were demonstrated. The transformation of the electronic structure from the antiferromagnetic high-spin insulator to the paramagnetic two-band correlated metal through a narrow-gap antiferromagnetic excitonic semiconductor was obtained.
Review
Physics, Multidisciplinary
J. Spalek, M. Fidrysiak, M. Zegrodnik, A. Biborski
Summary: The principal purpose of this topical review is to identify the universal features of high-temperature (high-Tc) and related strongly-correlated systems and compare them quantitatively with experimental data. The discussion covers the concept of exchange-interaction-mediated pairing and strong correlations among narrow band electrons, as well as the variational approach to study specific properties. The review presents the calculated ground-state and dynamic characteristics of high-Tc systems and discusses the limitations of certain models.
PHYSICS REPORTS-REVIEW SECTION OF PHYSICS LETTERS
(2022)
Article
Chemistry, Physical
Sumanta K. K. Ghosh, Debashree Ghosh
Summary: Machine learning (ML) has been applied to optimize the matrix product state (MPS) ansatz for the wavefunction of strongly correlated systems. The ML optimization of MPS for the Heisenberg Hamiltonian on one-dimensional and ladder lattices, corresponding to conjugated molecular systems, has been tested. The input descriptors are lattice configurations and the output is configuration interaction coefficients for the supervised ML.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Artur Wodynski, Martin Kaupp
Summary: The recent study extends the local hybrid functional by incorporating a strong-correlation factor obtained from the adiabatic connection in the spirit of the KP16 model. By damping the small values in the correction factor, it avoids double counting of nondynamical correlation and maintains the accuracy of the original LH20t local hybrid. The new scLH22t functional has shown improvements in reducing fractional-spin errors, bond dissociation curves, and systems with multireference character compared to LH20t.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Review
Physics, Applied
V. Yu Irkhin, Yu N. Skryabin
Summary: This paper focuses on topological order in strongly correlated systems and discusses various metallic non-Fermi-liquid states, as well as the classification of topological states and the differences between quantum and classical topology.
JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM
(2022)
Article
Chemistry, Physical
Jerzy Cioslowski, Berthold-Georg Englert, Martin-Isbjoern Trappe, Jun Hao Hue
Summary: At the limit of infinite confinement strength, the ground state of a system containing two interacting fermions or bosons in harmonic confinement remains strongly correlated. The natural orbitals of this system exhibit peculiar properties, such as nonzero collective occupancies for all angular momenta and a relationship with eigenfunctions and eigenvalues of a zero-energy Schrodinger equation with an attractive Gaussian potential. These properties have implications for the decay behavior and energy contributions of the system.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Physics, Applied
A. Sherman
Summary: This paper investigates the correlation between negative electron compressibility (NEC) regions and the observed phase separation in crystals with strong electron correlations. The NEC regions are found in several models describing strong electron correlations and lead to the separation of the system into electron-rich and electron-poor domains. Phonons play a role in absorbing the energy released during this separation and shaping lattice distortions and domains of different electron concentrations.
INTERNATIONAL JOURNAL OF MODERN PHYSICS B
(2022)
Article
Chemistry, Physical
Haobin Wang, Hans-Dieter Meyer
Summary: The regularization of the coefficient tensor instead of the reduced density matrix in multiconfiguration time-dependent Hartree (MCTDH) and multilayer MCTDH (ML-MCTDH) methods significantly improves the efficiency and correctness of equations of motion (EOMs). This is particularly important for handling challenging problems and large systems that require many layers of ML-MCTDH. The new regularization scheme is essential for quickly rotating virtual orbitals into the correct directions in Hilbert space, especially in the weak coupling regime.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Article
Chemistry, Physical
Samrit Mainali, Fabien Gatti, Dmitri Iouchtchenko, Pierre-Nicholas Roy, Hans-Dieter Meyer
Summary: In this study, the applicability of the ML-MCTDH method in computing ground states of one-dimensional chains of linear rotors with dipolar interactions was demonstrated and compared with DMRG. The results showed that entropies calculated by ML-MCTDH for larger system sizes exhibit nonmonotonicity, particularly near a second-order quantum phase transition.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Qingyong Meng, Markus Schroeder, Hans-Dieter Meyer
Summary: In this study, high-dimensional quantum dynamics calculations were performed on the mode-specific surface scattering of a carbon monoxide molecule on a copper(100) surface, taking into account lattice effects. The results demonstrate that the sticking probability is reduced when the surface atom on the impact site is initially vibrationally excited.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2021)
Article
Physics, Condensed Matter
Mingrui Yang, Matija Cufar, Elke Pahl, Joachim Brand
Summary: This study presents exact numerical data for the lowest-energy momentum eigenstates of a repulsive spin impurity in a one-dimensional Bose gas, and identifies different dynamical regimes and transitions between them based on the energies and correlation functions. The results reveal the behavior of impurities in different dynamical regimes and their transitions.
Article
Physics, Multidisciplinary
Ulrich Ebling, Ulrich Zulicke, Joachim Brand
Summary: We theoretically study a system of spin-1/2 fermions confined to two spatial dimensions and experiencing isotropic short-range attraction, with the presence of spin-orbit coupling and Zeeman spin splitting. We find that two-particle bound states have a dominant triplet contribution in a specific region of parameter space where the spin-splitting energy is large. The purest triplet character of the dimers is observed under weak s-wave interaction strength. The existence of bound states is determined by the center-of-mass momentum.
Article
Chemistry, Physical
Shanyu Han, Markus Schroeder, Fabien Gatti, Hans-Dieter Meyer, David Lauvergnat, David R. Yarkony, Hua Guo
Summary: In this study, the applicability of the multi-configurational time-dependent Hartree method in treating nonadiabatic photodissociation dynamics was examined. The results showed that this method has promise for handling high-dimensional nonadiabatic photodissociation problems.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Multidisciplinary Sciences
Markus Schroeder, Fabien Gatti, David Lauvergnat, Hans-Dieter Meyer, Oriol Vendrell
Summary: The Zundel and Eigen cations are important in proton transfer processes in liquid water. Quantum simulations show that two water molecules and an excess proton constitute the fundamental structure that explains the infrared spectra of both cations.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Physical
David Mendive-Tapia, Hans-Dieter Meyer, Oriol Vendrell
Summary: The MCTDH method and its ML-MCTDH extension are powerful algorithms for computing nuclear quantum dynamics in high-dimensional systems efficiently. The computational cost can be reduced by providing time-dependent variational orbitals and choosing layered effective degrees of freedom. However, the selection of mode grouping and tensor tree is subjective and based on intuition and experience. In this study, a new protocol based on multivariate statistics, including factor analysis and hierarchical clustering, is proposed to guide the optimal design of complex tensor-network decompositions reliably and conveniently. The advantages of this new algorithm and its applicability are tested on water and floppy protonated water clusters with large amplitude motions.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2023)
Article
Physics, Multidisciplinary
Madhumita Sarkar, Mainak Pal, Arnab Sen, Krishnendu Sengupta
Summary: We numerically analyze spin-1/2 fermions in a one-dimensional harmonic potential with a magnetic point-like impurity. Even for a few particles, we observe ground state level crossings between different fermion parities. We interpret this as a few-body precursor to a quantum phase transition, where the impurity breaks a Cooper pair. This interpretation is supported by analyzing density-density correlations in momentum space. Finally, we discuss the experimental realization of the system using existing cold-atom platforms.
Article
Physics, Multidisciplinary
Kadin Thompson, Joachim Brand, Ulrich Zuelicke
Summary: A topological superfluid phase with emergent chiral -p-wave pair potential is investigated in a two-dimensional Fermi superfluid, where s-wave pairing, spin-orbit coupling, and a large Zeeman splitting are present. The subgap-energy bound states at step-like interfaces are studied using the spin-resolved Bogoliubov-de Gennes mean-field formalism and the Andreev approximation. The presence of Majorana zero modes and the effects of boundary conditions on their properties are analyzed.
Article
Optics
Sarthak Choudhury, Joachim Brand
Summary: The dynamics of a vortex molecule in two coherently coupled superfluids in a quasi-two-dimensional geometry were investigated, revealing internal dynamics such as rotation and boundary-induced breakup. Stable and unstable fixed points as well as separatrices characterizing the dynamics of the vortex molecule were classified.
Article
Materials Science, Multidisciplinary
Joachim Brand, Mingrui Yang, Elke Pahl
Summary: The study investigates a statistical bias in FCIQMC that can become the dominant error, especially in scenarios without sign problem, such as in bosonic systems. Researchers provide new insights into the nature of the bias and suggest possible methods to address the population control bias.
Article
Physics, Multidisciplinary
K. Thompson, U. Zulicke, J. Brand
Summary: This study investigates the coexistence of topological and nontopological superfluids in a two-dimensional spin-imbalanced Fermi gas using zero-temperature mean-field approach and exact numerical results, revealing the dependence of topological transition on the Zeeman spin-splitting energy. By controlling the strength of interactions and the spin energy, it is possible to spatially separate and coexist topological and nontopological superfluids.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Physics, Multidisciplinary
Ulrich Ebling, Ali Alavi, Joachim Brand
Summary: This study explores the properties of the lowest energy states with nonzero total momentum (yrast states) in the Hubbard model, focusing on spin-1/2 fermions with attractive on-site interaction in a quantum ring configuration at low density. The transition from 1D to 2D regime is investigated using Bethe ansatz and Full-Configuration-Interaction Quantum Monte Carlo method to examine the changes in yrast excitation spectrum and the impact of pairing. Additionally, fragmented condensation signatures for certain yrast states typically associated with dark solitons are identified.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Materials Science, Multidisciplinary
Nathan Ng, Sebastian Wenderoth, Rajagopala Reddy Seelam, Eran Rabani, Hans-Dieter Meyer, Michael Thoss, Michael Kolodrubetz
Summary: This study investigates the dynamics of systems coupling a central degree of freedom with a bath, revealing a well-defined thermodynamic limit and scaling collapse behavior in the central qubit and spin system. The growth of entanglement at longer timescales may be attributed to dephasing mechanisms or long-range interactions mediated by the central degree of freedom. Signs of localization are also observed with unscaled system-bath coupling.
