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We develop a semiclassical density functional theory in the context of quantum dots. Coulomb blockade conductance oscillations have been measured in several experiments using nanostructured quantum dots. The statistical properties of these…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 Denis Ullmo , Tatsuro Nagano , Steven Tomsovic , Harold U. Baranger

Recent developments of experimental techniques in the field of ultra-cold gases open a path to study the crossover from 'few' to 'many' on the quantum level. In this case, accurate description of inter-particle correlations is very…

Quantum Gases · Physics 2018-03-23 Marcin Płodzień , Dariusz Wiater , Andrzej Chrostowski , Tomasz Sowiński

The classical simulation of quantum systems typically requires exponential resources. Recently, the introduction of a machine learning-based wavefunction ansatz has led to the ability to solve the quantum many-body problem in regimes that…

Disordered Systems and Neural Networks · Physics 2019-10-24 Joseph Gomes , Keri A. McKiernan , Peter Eastman , Vijay S. Pande

We consider the spectral correlations of clean globally hyperbolic (chaotic) quantum systems. Field theoretical methods are applied to compute quantum corrections to the leading (`diagonal') contribution to the spectral form factor.…

Chaotic Dynamics · Physics 2007-05-23 Jan Müller , Alexander Altland

The emerging field of quantum simulation of many-body systems is widely recognized as a very important application of quantum computing. A crucial step towards its realization in the context of many-electron systems requires a rigorous…

Atomic Physics · Physics 2021-08-23 Sumeet , V. S. Prasannaa , B. P. Das , B. K. Sahoo

We develop semiclassical approximations for calculating photoabsorption cross sections beyond the continuum threshold in quantum many-body systems. These approximations use the fully quantum-mechanical Wigner function of the ground state…

Atomic Physics · Physics 2023-05-24 Julien Toulouse

Controllable systems relying on quantum behavior to simulate distinctly quantum models so far rely on increasingly challenging classical computing to verify their results. We develop a general protocol for confirming that an arbitrary…

Quantum Physics · Physics 2015-04-07 Dvir Kafri , Jacob Taylor

We provide an overview of a canonical formalism that describes mixed quantum-classical systems in terms of statistical ensembles on configuration space, and discuss applications to measurement theory. It is shown that the formalism allows a…

Quantum Physics · Physics 2009-07-06 M Reginatto , M J W Hall

We illustrate how classical chaotic dynamics influences the quantum properties at mesoscopic scales. As a model case we study semiclassically coherent transport through ballistic mesoscopic systems within the Landauer formalism beyond the…

Mesoscale and Nanoscale Physics · Physics 2010-02-24 Daniel Waltner , Klaus Richter

The classical field approximation is widely used to better understand the predictions of ultra-light dark matter. Here, we use the truncated Wigner approximation method to test the classical field approximation of ultra-light dark matter.…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-12 Andrew Eberhardt , Alvaro Zamora , Michael Kopp , Tom Abel

We discuss how to calculate genuine multipartite quantum and classical correlations in symmetric, spatially invariant, mixed $n$-qubit density matrices. We show that the existence of symmetries greatly reduces the amount of free parameters…

Quantum Physics · Physics 2016-10-24 Gian Luca Giorgi , Steve Campbell

Recent developments in quantum gas microscopy open up the possibility of real-time observation of quantum many-body systems. To understand the dynamics of atoms under such circumstances, we formulate the dynamics under a real-time spatially…

Quantum Physics · Physics 2017-03-01 Yuto Ashida , Masahito Ueda

In this short note we study Spin-Boson Models from the Quasi-Classical standpoint. In the Quasi-Classical limit, the field becomes macroscopic while the particles it interacts with, they remain quantum. As a result, the field becomes a…

Mathematical Physics · Physics 2022-09-15 Michele Correggi , Marco Falconi , Marco Merkli

We consider the quantum many-body evolution of a homogeneous Fermi gas in three dimensions in the coupled semiclassical and mean-field scaling regime. We study a class of initial data describing collective particle-hole pair excitations on…

Mathematical Physics · Physics 2022-07-07 Niels Benedikter , Phan Thành Nam , Marcello Porta , Benjamin Schlein , Robert Seiringer

Within the non-equilibrium Green's function technique on the real time contour, the Phi-functional method of Baym is reviewed and generalized to arbitrary non-equilibrium many-particle systems. The scheme may be closed at any desired order…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yu. B. Ivanov , J. Knoll , D. N. Voskresensky

In many situations, one can approximate the behavior of a quantum system, i.e. a wave function subject to a partial differential equation, by effective classical equations which are ordinary differential equations. A general method and…

Mathematical Physics · Physics 2007-05-23 Martin Bojowald , Aureliano Skirzewski

Recent experiments have revealed that beyond-mean-field corrections are much more relevant in weakly-interacting dipolar condensates than in their non-dipolar counterparts. We show that in quasi-one-dimensional geometries quantum…

Quantum Gases · Physics 2017-08-04 Daniel Edler , Chinmayee Mishra , Falk Wächtler , Rejish Nath , Subhasis Sinha , Luis Santos

For 1 Dimensional loop space, a nonlinear nonlocal transformation of fields is given to make the action of the self-interacting quantum field to the free one. A specific type of Classically broken symmetry is restored in Quantum theory. 1-D…

High Energy Physics - Theory · Physics 2014-06-24 Pinaki Patra , Tanmay Mandal , Jyoti Prasad Saha

We study a spin 1 Bose condensate small enough to be treated as a single magnetic `domain': a system that we term a microcondensate. Because all particles occupy a single spatial mode, this quantum many body system has a well defined…

Quantum Gases · Physics 2015-03-17 Austen Lamacraft

Quantum subspace expansion (QSE) offers promising avenues to perform spectral calculations on quantum processors but comes with a large measurement overhead. Informationally complete (IC) measurements, such as classical shadows, were…

Quantum Physics · Physics 2025-10-30 Laurin E. Fischer , Daniel Bultrini , Ivano Tavernelli , Francesco Tacchino