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We present a quantum-field-theoretical framework based on path integrals and Feynman diagrams for the investigation of the quantum-optical properties of one-dimensional waveguiding structures with embedded quantum impurities. In particular,…

Recently the Rydberg blockade effect has been utilized to realize quantum spin liquid on the kagome lattice. Evidence of quantum spin liquid has been obtained experimentally by directly measuring non-local string order. In this letter, we…

Quantum Gases · Physics 2023-03-24 Yanting Cheng , Chengshu Li , Hui Zhai

The transformer architecture, known for capturing long-range dependencies and intricate patterns, has extended beyond natural language processing. Recently, it has attracted significant attention in quantum information and condensed matter…

Quantum Physics · Physics 2025-08-08 Lu Wei , Zhian Jia , Yufeng Wang , Dagomir Kaszlikowski , Haibin Ling

Nonautonomous linear ordinary differential equations of the form $\dot{v}(t) = A(t)\, v(t)$, where $A(t)$ is non-skew-symmetric, are often used to describe nonunitary dynamics in a variety of fields that range from open quantum system…

Quantum Physics · Physics 2026-05-29 Pouya Khazaei , Eitan Geva

We explore the connections between the theories of stochastic analysis and discrete quantum mechanical systems. Naturally these connections include the Feynman-Kac formula, and the Cameron-Martin-Girsanov theorem. More precisely, the notion…

Mathematical Physics · Physics 2019-06-11 Anastasia Doikou , Simon J. A. Malham , Anke Wiese

The first part of this article centers on the fact that key features of the dynamical response of weakly-correlated materials (the alkalis, Al), have been found experimentally to differ qualitatively from simple-model behavior. In the…

Strongly Correlated Electrons · Physics 2007-05-23 Adolfo G. Eguiluz , Wei Ku

In the spirit of recently developed LDA+U and LDA+DMFT methods we implement a combination of density functional theory in its local density approximation (LDA) with a $k$- and $\omega -$dependent self-energy found from diagrammatic…

Strongly Correlated Electrons · Physics 2018-04-17 Sergey Y. Savrasov , Giacomo Resta , Xiangang Wan

Transport and scattering phenomena in open quantum-systems with a continuous energy spectrum are conveniently solved using the time-dependent Schrodinger equation. In the time-dependent picture, the evolution of an initially localized…

Quantum Physics · Physics 2011-05-13 Tobias Kramer

Variational quantum algorithms are a promising tool for solving partial differential equations. The standard approach for its numerical solution are finite difference schemes, which can be reduced to the linear algebra problem. We consider…

Quantum Physics · Physics 2023-10-10 N. M. Guseynov , A. A. Zhukov , W. V. Pogosov , A. V. Lebedev

The first goal of Vibration-Transit (V-T) theory was to construct a tractable approximate Hamiltonian from which the equilibrium thermodynamic properties of monatomic liquids can be calculated. The Hamiltonian for vibrations in an…

Soft Condensed Matter · Physics 2007-05-23 Giulia DeLorenzi-Venneri , Duane Wallace

Energy functionals of the Green's function can simultaneously provide spectral and thermodynamic properties of interacting electrons' systems. Though powerful in principle, these formulations need to deal with dynamical…

Materials Science · Physics 2024-05-28 Tommaso Chiarotti , Andrea Ferretti , Nicola Marzari

Vector spherical wavefunctions were derived in closed-form to represent time-harmonic electromagnetic fields in an orthorhombic dielectric-magnetic material with gyrotropic-like magnetoelectric properties. These wavefunctions were used to…

Optics · Physics 2012-11-27 Akhlesh Lakhtakia , Tom G. Mackay

Most classical mechanical systems are based on dynamical variables whose values are real numbers. Energy conservation is then guaranteed if the dynamical equations are phrased in terms of a Hamiltonian function, which then leads to…

Mathematical Physics · Physics 2013-12-05 Gerard 't Hooft

The in-in formalism and its influence functional generalization are widely used to describe the out-of-equilibrium dynamics of unitary and open quantum systems, respectively. In this paper, we build on these techniques to develop an…

High Energy Physics - Theory · Physics 2024-05-08 Nishant Agarwal , Yi-Zen Chu

Non-commutative algebras and entanglement are two of the most important hallmarks of many-body quantum systems. Dynamical perturbation methods are the most widely used approaches for quantum many-body systems. While study of…

Quantum Physics · Physics 2022-02-25 Wenxin Ding

We consider a finite quantum system under slow driving and weakly coupled to thermal reservoirs at different temperatures. We present a systematic derivation of the quantum master equation for the density matrix and the out-of-time-order…

Mesoscale and Nanoscale Physics · Physics 2021-07-28 Bibek Bhandari , Rosario Fazio , Fabio Taddei , Liliana Arrachea

The main goal of this work is to study systematically the quantum aspects of the interaction between scalar particles in the framework of Generalized Scalar Duffin-Kemmer-Petiau Electrodynamics (GSDKP). For this purpose the theory is…

High Energy Physics - Theory · Physics 2015-10-19 R. Bufalo , T. R. Cardoso , A. A. Nogueira , B. M. Pimentel

We propose a variational alternative to the Trotter-Suzuki decomposition that provides greater control over errors while preserving the unitary structure of time evolution. The variational parameters in our ansatz are derived from a global…

Quantum Physics · Physics 2025-11-20 Ibsal Assi , Michael Vogl , Meenu Kumari , J. P. F. LeBlanc

We present the variational multiscale (VMS) method for partial differential equations (PDEs) with stochastic coefficients and source terms. We use it as a method for generating accurate coarse-scale solutions while accounting for the effect…

Numerical Analysis · Mathematics 2013-10-09 Jayanth Jagalur-Mohan , Onkar Sahni , Alireza Doostan , Assad Oberai

We apply the open systems concept and the influence functional formalism introduced in Paper I to establish a stochastic theory of relativistic moving spinless particles in a quantum scalar field. The stochastic regime resting between the…

Quantum Physics · Physics 2014-11-18 Philip R. Johnson , B. L. Hu