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It is known that self-adjoint Hamiltonians with purely discrete eigenvalues can be written as (infinite) linear combination of mutually orthogonal projectors with eigenvalues as coefficients of the expansion. The projectors are defined by…

Mathematical Physics · Physics 2020-10-13 Fabio Bagarello , Sergey Kuzhel

We present a comprehensive analytical study that extends the conventional formulation of Berry curvature, highlighting its derivation in the context of problematic domains of definition of the operators. Our analysis reveals that handling…

Quantum Physics · Physics 2025-07-29 Georgios Konstantinou , Konstantinos Moulopoulos

Noncommutative oscillators are first-quantized through an abelian Drinfel'd twist deformation of a Hopf algebra and its action on a module. Several important and subtle issues making possible the quantization are solved. The spectrum of the…

High Energy Physics - Theory · Physics 2011-05-05 P. G. Castro , B. Chakraborty , R. Kullock , F. Toppan

Based on the multiband semiconductor Bloch equations a microscopic approach to high-harmonic generation in crystalline solids which is able to properly describe degenerate bands and band crossings is presented and analyzed. It is well-known…

Mesoscale and Nanoscale Physics · Physics 2021-02-10 Le Huu Thong , Cong Ngo , Huynh Thanh Duc , Xiaohong Song , Torsten Meier

We theoretically investigate Bloch oscillations in a one-dimensional Bose-Hubbard chain, with single-particle losses from the odd lattice sites described by the Lindblad equation. For a single particle the time evolution of the state is…

Quantum Physics · Physics 2020-09-08 Bradley Longstaff , Eva-Maria Graefe

Analytical expressions are given for the eigenvalues and eigenvectors of a Hamiltonian with su_q(2) dynamical symmetry. The relevance of such an operator in Quantum Optics is discussed. As an application, the ground state energy in the…

Quantum Physics · Physics 2015-06-26 Angel Ballesteros , Sergei M. Chumakov

The quantization of a single particle without spin in an appropriate curved space-time is considered. The Hamilton formalism on reduced space for a particle in a curved space-time is constructed and the main aspects of quantization scheme…

General Relativity and Quantum Cosmology · Physics 2007-05-23 D. A. Kalinin

We discuss some features of non-self-adjoint Hamiltonians with real discrete simple spectrum under the assumption that the eigenvectors form a Riesz basis of Hilbert space. Among other things, {we give conditions under which these…

Mathematical Physics · Physics 2015-06-18 F. Bagarello , A. Inoue , C. Trapani

We develop an algebraic approach for finding the eigenfunctions of a large class of few and many-body Hamiltonians, in one and higher dimensions, having linear spectra. The method presented enables one to exactly map these interacting…

Condensed Matter · Physics 2007-05-23 N. Gurappa , Prasanta K. Panigrahi , T. Soloman Raju

We study a class of nonlinear Hamiltonians, with applications in quantum optics. The interaction terms of these Hamiltonians are generated by taking a linear combination of powers of a simple `beam splitter' Hamiltonian. The entanglement…

Quantum Physics · Physics 2015-05-13 Thomas Brougham , Goce Chadzitaskos , Igor Jex

The Bloch theorem enables reduction of the eigenvalue problem of the single-particle Hamiltonian that commutes with translational group. Based on a group theory analysis we present generalization of the Bloch theorem that incorporates all…

Mesoscale and Nanoscale Physics · Physics 2015-03-18 E. Dobardžić , M. Dimitrijević , M. V. Milovanović

The basic notions of quantum mechanics are formulated in terms of separable infinite dimensional Hilbert space $\mathcal{H}$. In terms of the Hilbert lattice $\mathcal{L}$ of closed linear subspaces of $\mathcal{H}$ the notions of state and…

Logic in Computer Science · Computer Science 2023-06-22 Eike Neumann , Martin Pape , Thomas Streicher

The soliton effect is defined in nonlinear physics by the transformation of a nonlinear time-dependent dynamical system into an equivalent linear spectral eigenproblem whose invariant eigenvalues unambiguously define all the dynamical…

Mesoscale and Nanoscale Physics · Physics 2015-06-22 Claude G. Reinisch

In the holonomic approach to quantum computation information is encoded in a degenerate eigenspace of a parametric family of Hamiltonians and manipulated by the associated holonomic gates. These are realized in terms of the non-abelian…

Quantum Physics · Physics 2009-10-31 Jiannis Pachos , Paolo Zanardi , Mario Rasetti

The Lie group adiabatic evolution determined by a Lie algebra parameter dependent Hamiltonian is considered. It is demonstrated that in the case when the parameter space of the Hamiltonian is a homogeneous K\"ahler manifold its fundamental…

Quantum Physics · Physics 2009-11-06 E. Strahov

Under unitary time evolution, expectation values of physically reasonable observables often evolve towards the predictions of equilibrium statistical mechanics. The eigenstate thermalization hypothesis (ETH) states that this is also true…

Statistical Mechanics · Physics 2018-04-19 Fabio Anza , Christian Gogolin , Marcus Huber

A general hamiltonian $H$ of electrons in finite concentration, interacting via any two-body coupling inside a crystal of arbitrary dimension, is considered. For simplicity and without loss of generality, a one-band model is used to account…

Strongly Correlated Electrons · Physics 2020-07-01 J. Szeftel , A. Khater

Quasicrystals are long-range ordered, yet not periodic, and thereby present a fascinating challenge for condensed matter physics, as one cannot resort to the usual toolbox based on Bloch's theorem. Here, we present a numerical method for…

Disordered Systems and Neural Networks · Physics 2023-04-18 Emmanuel Gottlob , Ulrich Schneider

y formally diagonalizing with accuracy $\hbar$ the Hamiltonian of electrons in a crystal subject to electromagnetic perturbations, we resolve the debate on the Hamiltonian nature of semiclassical equations of motion with Berry-phase…

Other Condensed Matter · Physics 2016-08-16 Pierre Gosselin , Fehrat Ménas , Alain Bérard , Hervé Mohrbach

In [1,2] we established and discussed the algebra of observables for $2+1$ gravity at both the classical and quantum level, and gave a systematic discussion of the reduction of the expected number of independent observables to $6g - 6 (g >…

General Relativity and Quantum Cosmology · Physics 2013-11-13 J. E. Nelson , T. Regge