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Related papers: N-Level Quantum Systems and Legendre Functions

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Quantum stochastic differential equations have been used to describe the dynamics of an atom interacting with the electromagnetic field via absorption/emission processes. Here, by using the full quantum stochastic Schroedinger equation…

Quantum Physics · Physics 2009-10-31 Alberto Barchielli , Giancarlo Lupieri

We provide a fully quantum description of a mechanical oscillator in the presence of thermal environmental noise by means of a quantum Langevin formulation based on quantum stochastic calculus. The system dynamics is determined by symmetry…

Quantum Physics · Physics 2015-08-11 Alberto Barchielli , Bassano Vacchini

The problem of quantum harmonic oscillator with "regular+random" square frequency, subjected to "regular+random external force, is considered in framework of representation of the wave function by complex-valued random process. Average…

Quantum Physics · Physics 2007-05-23 A. S. Gevorkyan , A. A. Udalov

In statistical mechanics, it is well known that finite-state classical lattice models can be recast as quantum models, with distinct classical configurations identified with orthogonal basis states. This mapping makes classical statistical…

Quantum Physics · Physics 2011-09-28 Norman Margolus

The new Theorem on location of maximum of probability density functions of dimensionless second difference of the three adjacent energy levels for $N$-dimensional Gaussian orthogonal ensemble GOE($N$), $N$-dimensional Gaussian unitary…

Statistical Mechanics · Physics 2007-05-23 Maciej M. Duras

Quantum contextuality is a limitation on deterministic hidden variable models, testable in measurement scenarios where outcomes differ under quantum or classical descriptions due to a common set of constraints. When considering measurements…

Quantum Physics · Physics 2025-09-25 Colm Kelleher , Frédéric Holweck

Long-range quantum systems, in which the interactions decay as $1/r^{\alpha}$, are of increasing interest due to the variety of experimental set-ups in which they naturally appear. Motivated by this, we study fundamental properties of…

Quantum Physics · Physics 2026-01-08 Jorge Sánchez-Segovia , Jan T. Schneider , Álvaro M. Alhambra

The paper introduces a simple quantum model to calculate in a general way allowed frequencies and energy levels of the anharmonic oscillator. The theoretical basis of the approach has been introduced in two early papers aimed to infer the…

Quantum Physics · Physics 2011-05-19 Sebastiano Tosto

Two-dimensional electron systems offer an appealing platform to explore long-lived excitations arising due to collinear carrier scattering enabled by phase-space constraints at the Fermi surface. Recently it was found that these effects can…

Strongly Correlated Electrons · Physics 2024-09-27 Serhii Kryhin , Leonid Levitov

Many complex quantum systems can be described by effectively nonlinear dynamics. While such dynamics have many appealing characteristics, they also make the analysis significantly more involved. This is due to the fact that only a few…

Quantum Physics · Physics 2025-10-15 Sebastian Deffner , Steve Campbell

We consider N fermions in a two-dimensional harmonic oscillator potential interacting with a very short-range repulsive pair-wise potential. The ground-state energy of this system is obtained by performing a Thomas-Fermi as well as a…

Condensed Matter · Physics 2007-05-23 M. K. Srivastava , R. K. Bhaduri , J. Law , M. V. N. Murthy

We show that a polynomial H(N) of degree N of a harmonic oscillator hamiltonian allows us to devise a fully solvable continuous quantum system for which the first N discrete energy eigenvalues can be chosen at will. In general such a choice…

Quantum Physics · Physics 2021-02-02 Ole Steuernagel , Andrei Klimov

The coupling of two-level quantum systems to the thermal environment is a fundamental problem, with applications ranging from qubit state preparation to spin models. However, for the elementary problem of the thermodynamics of an ensemble…

Quantum Gases · Physics 2025-10-29 Christian Kurtscheid , Andreas Redmann , Frank Vewinger , Julian Schmitt , Martin Weitz

The mean field approximation is used to investigate the general features of the dynamics of a two-level atom in a ferromagnetic lattice close to the Curie temperature. Various analytical and numerical results are obtained. We first…

Quantum Physics · Physics 2023-07-07 Yamen Hamdouni

Though quantum algorithm acts as an important role in quantum computation science, not only for providing a great vision for solving classically unsolvable problems, but also due to the fact that it gives a potential way of understanding…

Quantum Physics · Physics 2015-08-11 Xiang Zhan , Jian Li , Hao Qin , Zhihao Bian , Peng Xue

An approach to correlated dynamics of quantum nuclei and electrons both in dynamical interaction with external environments is presented. This stochastic quantum molecular dynamics rests on a theorem that establishes a one-to-one…

Materials Science · Physics 2012-12-27 Heiko Appel , Massimiliano Di Ventra

Today it still remains a challenge whether quantum mechanics has an underlying statistical explanation or not. While there are and were a lot of models trying to explain quantum phenomena with statistical methods these all failed on certain…

Quantum Physics · Physics 2016-12-05 Gabor Helesfai

A model describing N particles on a line interacting pairwise via an elliptic function potential in the presence of an external field is partially solved in the quantum case in a totally algebraic way. As an example, the ground state and…

High Energy Physics - Theory · Physics 2009-10-31 D. Gomez-Ullate , A. Gonzalez-Lopez , M. A. Rodriguez

The capability of density-functional theory to deal with the ground-state of strongly correlated low-dimensional systems, such as semiconductor quantum dots, depends on the accuracy of functionals developed for the exchange and correlation…

Strongly Correlated Electrons · Physics 2009-02-25 S. Pittalis , E. Rasanen , C. Proetto , E. K. U. Gross

A recent promising arena for quantum advantage is simulating exponentially large classical systems. Here, we show how this advantage can be used to calculate the dynamics of open classical systems experiencing dissipation, including the…

Quantum Physics · Physics 2025-03-17 Agi Villanyi , Yariv Yanay , Ari Mizel