Article
Physics, Fluids & Plasmas
William D. Pineros, Tsvi Tlusty
Summary: The paper demonstrates how to design complex nonequilibrium steady-state density distributions and flux field flows using the large-deviation behavior of a Brownian particle. The method is validated by replicating analytical results and showing the capacity to yield complex prescribed targets. This approach is considered a first step towards designing more complex NESS where general frameworks are lacking.
Article
Materials Science, Multidisciplinary
Zihan Cheng, Andrew C. Potter
Summary: We propose a numerical method to simulate nonequilibrium Floquet steady states of one-dimensional periodically driven many-body systems coupled to a dissipative bath. The method is based on a matrix product operator ansatz for the Floquet density matrix in frequency space, and allows computation of the dynamical approach to the steady state.
Article
Physics, Fluids & Plasmas
Michael Jade Y. Jerez, Mike A. Bonachita, Mark Nolan P. Confesor
Summary: Based on a detailed balance-like relation, a measure K* is proposed to quantify the distance between a nonequilibrium steady-state (NESS) and equilibrium. Experimental results and simulations demonstrate that K* increases at slow switching rates, indicating departure from equilibrium, and approaches zero under equilibrium conditions. Thus, the steady-state distribution combined with K* fully characterizes a NESS.
Article
Optics
Daniel Heineken, Konstantin Beyer, Kimmo Luoma, Walter T. Strunz
Summary: This study investigates the dissipative preparation of entangled nonequilibrium steady states using a collision model with qubits coupled to heat reservoirs. The research shows that only a certain bath temperature range allows for entangled NESS and quantum memory effects play a crucial role. Additionally, the study identifies a heat current range that guarantees entanglement of nonequilibrium steady states.
Article
Physics, Multidisciplinary
Zhen-Xia Niu, Wei Zhang
Summary: In this study, a numerical analysis was conducted on the dynamical steady states of polariton Bose-Einstein condensates in an incoherent exciton reservoir driven by a ring-shaped optical pump. The balance between loss and gain of the polariton BEC resulted in a variety of steady states with different configurations, including topological defects such as vortex-antivortex pairs, vortices with a winding number, and solitons. The system became unstable under fast decay rates and small pumping ring, causing the BECs to no longer exist in the long-time limit. Additionally, it was confirmed that solitons were dynamically stable in this system, with a steady polariton current induced by repulsive interactions.
FRONTIERS IN PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Harshvardhan Jog, Luminita Harnagea, Dibyata Rout, Takashi Taniguchi, Kenji Watanabe, Eugene J. Mele, Ritesh Agarwal
Summary: We investigate the symmetries of 1T-TiSe2 and observe that the ground state of the CDW phase is achiral, but it can be transformed into a non-equilibrium chiral phase under high-intensity laser excitation, altering the electronic correlations in the material. The photogalvanic technique demonstrates the sensitivity to structural symmetries and provides evidence of different optically driven phases in 1T-TiSe2.
Article
Physics, Multidisciplinary
Mitchell J. Knight, Harry M. Quiney, Andy M. Martin
Summary: This paper describes the variational determination of the two-fermion reduced density matrix for harmonically trapped, ultracold few-fermion systems in one dimension with equal spin populations. The problem is formulated as a semi-definite program subject to N-representability conditions. The ground-state energies, density, pair-correlation function, and eigenvalues of the 2-RDM are found using an augmented Lagrangian method. The results show that this method accurately describes the salient features of the systems and has the potential to handle larger systems.
NEW JOURNAL OF PHYSICS
(2022)
Article
Engineering, Electrical & Electronic
Shabbir Muhammad, Shafiq urRehman, Fatima Sarwar, Shamsa Bibi, Raziya Nadeem, Muhammad Waheed Mushtaq, Abdullah G. Al-Sehemi, Saleh S. Alarfaji, Sajjad Hussain
Summary: This study systematically designed and calculated the properties of C-60 derivatives using density functional theory. The functionalized fullerene derivatives showed efficient nonlinear optical response properties, which is significant for designing efficient NLO materials.
MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Nils Niggemann, Bjorn Sbierski, Johannes Reuther
Summary: The study introduces a general functional renormalization group approach based on Majorana fermions to improve the accuracy of treating frustrated quantum spin systems at finite temperatures. By implementing spin operators via an SO(3) symmetric Majorana representation, the method shows significantly enhanced accuracy compared to previous methods at finite temperatures. The development of functional renormalization group approaches with Majorana fermions expands the applicability of such methods in a broader scope.
Article
Chemistry, Physical
Ji Il Choi, Christopher Johnson, Nadezda Fomina, Armin Darvish, Christoph Lang, Young Shik Shin, Han Seul Kim, Seung Soon Jang
Summary: We investigate the transport of electrons in a ferrocene aqueous solution nanoconfined between two Pt electro-des using density functional theory and a nonequilibrium Green function method. The system consists of three characteristic phases: metal electrodes, the electrode-solution interface, and the nanoconfined solution phase. Our findings reveal that the molecular configuration of water molecules at the Pt surface is adjusted due to the Pt-water interaction, and the charges at the Pt surface are redistributed. Furthermore, we discovered that the ferrocene molecule enhances electron transport through nanoconfined solutions, providing potential applications in nanoscale systems for electrochemical sensors.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Mikulas Matousek, Michal Hapka, Libor Veis, Katarzyna Pernal
Summary: A multiconfigurational adiabatic connection (AC) formalism is an attractive approach to compute the dynamic correlation within DMRG models. The study investigates the effect of removing the fixed-RDM approximation in AC and finds that lifting this approximation is a viable way toward improving the accuracy of existing AC approximations.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Physics, Multidisciplinary
Ingrid Strandberg, Goran Johansson, Fernando Quijandria
Summary: By studying the steady-state output field of a driven nonlinear Kerr parametric oscillator, we found that the output may exhibit Wigner negativity, depending on the properties of the selected mode.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Physics, Fluids & Plasmas
Paul Brehmer, Michael F. Herbst, Stefan Wessel, Matteo Rizzi, Benjamin Stamm
Summary: Within the reduced basis methods approach, an effective low-dimensional subspace is constructed to study quantum many-body Hilbert space, such as the ground-state phase diagram. This subspace is built from solutions of snapshots, which are ground states corresponding to specific parameter values. We demonstrate how a greedy strategy based on matrix-product-state calculations can be used to assemble the reduced basis and select parameter points. Once the reduced basis is obtained, computation of phase diagrams becomes independent of the computational complexity of the underlying Hilbert space for any parameter value. We showcase the efficiency and accuracy of this approach for various one-dimensional quantum spin-1 models, including anisotropic and biquadratic exchange interactions, resulting in diverse quantum phase diagrams.
Article
Quantum Science & Technology
Giovanni Cataldi, Ashkan Abedi, Giuseppe Magnifico, Simone Notarnicola, Nicola Dalla Pozza, Vittorio Giovannetti, Simone Montangero
Summary: The study presents a novel mapping method for studying 2D many-body quantum systems by solving an effective, one-dimensional long-range model. By comparing different mappings based on space-filling curves, such as the snake curve and the Hilbert curve, it is shown that the Hilbert curve has superior locality-preserving properties and improves numerical precision, especially for large systems. This makes it the best performer for simulating 2D lattice systems via 1D TN structures.
Article
Physics, Fluids & Plasmas
Michael F. Herbst, Benjamin Stamm, Stefan Wessel, Matteo Rizzi
Summary: This article presents a methodology for investigating phase diagrams of quantum models using the reduced basis method. The method significantly reduces computational complexity and demonstrates accuracy in two test cases.
Article
Physics, Applied
Ke Wang, Xiansong Xu, Yuan Cheng, Min Zhang, Jian-Sheng Wang, Hai Wang, Gang Zhang
Summary: Using density functional theory calculations, we investigated the spin-wave spectrum and magnon-phonon interaction in the CGT monolayer. The MPI in the CGT monolayer exhibits weak in-plane isotropy and a strong wave vector dependence. The temperature increase from 5K to 55K leads to a 4 times decrease in the magnon relaxation time, emphasizing the significance of MPI in the spin dynamics of the ferromagnetic CGT monolayer.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Physical
Xuefei Liu, Zhaofu Zhang, Zhao Ding, Bing Lv, Zijiang Luo, Jian-Sheng Wang, Zhibin Gao
Summary: A study using first principles method systematically predicted the anisotropic electronic and mechanical properties of 2D As2S3, showing a significantly higher Young's modulus ratio along two axes compared to black phosphorous. These findings provide valuable insights for the realization of flexible orientation-dependent nano-devices.
APPLIED SURFACE SCIENCE
(2021)
Article
Physics, Multidisciplinary
Jian-Sheng Wang
Summary: The article recalls the impression of Professor Dietrich Stauffer during the author's postdoc at HLRZ, and discusses the application of the theory of soft phonons with quartic nonlinear interactions in the phase transition of BaTiO3 crystal.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2021)
Article
Mathematics, Applied
Juzar Thingna, Daniel Manzano
Summary: This work discusses methods for obtaining true steady states in an open quantum system, involving the use of symmetry operators as well as two approaches that do not require knowledge of the symmetry operators. These methods can be powerful numerical tools for dealing with quantum many-body complex open systems.
Article
Physics, Multidisciplinary
Jakub Spiechowicz, Peter Haenggi, Jerzy Luczka
Summary: This study investigates the phenomenon of multistability in the velocity dynamics of a Brownian particle. It finds that the multistability is robust with respect to the choice of the starting position and velocity of the particle for moderate and high temperatures, but is affected by initial conditions in the low temperature regime.
Article
Thermodynamics
Yong-Mei Zhang, Mauro Antezza, Jian-Sheng Wang
Summary: The presence of interlayer interactions in twisted bilayer graphene (TBG) enhances several characteristics, including the optical and electronic properties. A series of double magic angles have been theoretically investigated in TBG. The thermal radiation from TBG can be tuned to the far infrared range by changing twist angles.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Review
Physics, Multidisciplinary
Jakub Spiechowicz, Ivan G. Marchenko, Peter Haenggi, Jerzy Luczka
Summary: The diffusion of small particles is widely studied and applied in various scientific fields. This article focuses on the temperature dependence of the diffusion coefficient for a Brownian particle, exploring different physical systems and their diffusion characteristics.
Article
Materials Science, Multidisciplinary
Hangbo Zhou, Gang Zhang, Jian-Sheng Wang, Yong-Wei Zhang
Summary: We investigate the anharmonic phonon scattering across a weakly interacting interface and find that the contribution from anharmonic three-phonon scatterings can be described by a temperature-dependent Landauer formula. Surprisingly, in the weak coupling limit, the transmission due to anharmonic phonon scattering increases indefinitely with temperature, which is not the case for two-phonon processes. We further reveal that anharmonic effects dominate over harmonic processes even at room temperature in real heterogeneous interfaces, emphasizing the importance of anharmonicity in weakly interacting systems.
Article
Physics, Multidisciplinary
Tobias Becker, Alexander Schnell, Juzar Thingna
Summary: This paper introduces a new class of quantum master equations that accurately reproduce the asymptotic state of an open quantum system beyond the infinitesimally weak system-bath coupling limit, while improving the accuracy of traditional master equations and correcting the issue of positivity violation.
PHYSICAL REVIEW LETTERS
(2022)
Review
Physics, Multidisciplinary
Jian-Sheng Wang, Jiebin Peng, Zu-Quan Zhang, Yong-Mei Zhang, Tao Zhu
Summary: This article discusses the description and modeling of transport phenomena in electron systems coupled via scalar or vector photons. It is divided into three parts: scalar photons (Coulomb interactions), transverse photons (described by vector potentials), and the phi = 0 or temporal gauge, which is a complete theory of electrodynamics. The nonequilibrium Green's function (NEGF) formalism is used as a tool to study steady-state transport, with the advantage of going beyond fluctuational electrodynamics (FE) due to its generality. Several examples are provided, including heat transfer between graphene sheets, light emission from a double quantum dot, and emission of energy, momentum, and angular momentum from a graphene nanoribbon. All calculations are based on a generalization of the Meir-Wingreen formula, with materials properties represented by photon self-energy and coupled with the Keldysh equation and the solution to the Dyson equation.
FRONTIERS OF PHYSICS
(2023)
Article
Optics
Jeongrak Son, Peter Talkner, Juzar Thingna
Summary: This study investigates the charging of a quantum battery by a four-stroke quantum machine. It is found that periodic measurements during the charging process can speed up the charging, but the gain of ergotropy is more pronounced in the absence of measurements. The influence of measurements on battery performance differs between the engine and refrigerator modes, with measurements having a larger impact on the engine mode.
Article
Materials Science, Multidisciplinary
Yong-Mei Zhang, Tao Zhu, Zu-Quan Zhang, Jian-Sheng Wang
Summary: We have developed a general microscopic theory for the transfer of energy, momentum, and angular momentum mediated by photons. Using the nonequilibrium Green's function method, we have proposed a unified formalism for describing the energy emitted, force experienced, and torque experienced by objects due to fluctuating electromagnetic fields. Our theory does not rely on the assumption of local thermal equilibrium and is applicable to arbitrary objects and non-reciprocal environments. By applying our theory to transport problems of graphene edges, we have demonstrated its capability and shown results that go beyond the predictive ability of conventional theories.
Article
Materials Science, Multidisciplinary
Jayendra N. Bandyopadhyay, Juzar Thingna
Summary: We propose a Floquet engineering formalism to design a periodic driving protocol for realizing the desired system from a given static Hamiltonian. This method is applicable to interacting and noninteracting quantum systems with a closed Lie algebraic structure, and is not restricted by the driving frequency. By fixing the gauge of the micromotion, we can engineer the functional form and operators of the driving protocol.
Article
Optics
JungYun Han, Daniel Leykam, Dimitris G. Angelakis, Juzar Thingna
Summary: In this study, we investigated nonequilibrium quantum heat transport in nonlinear bosonic systems under nonKerr-type interaction, predicting a negative excitation mode and cooling effect. Analytically estimating the thermodynamic response and numerically demonstrating heat current transitions, we showed long relaxation times in the cooling phase. Our findings suggest a potential manipulation of quantum states by inducing cooling through system interactions.
Article
Quantum Science & Technology
Jeongrak Son, Peter Talkner, Juzar Thingna
Summary: Two diagnostic schemes for quantum Otto heat engines were compared, with the scheme of repeated contacts showing significantly reduced number of measurements and better maintenance of quantum coherence.
