English
Related papers

Related papers: Perturbative method for generalized spectral decom…

200 papers

The fascinating concept of coherent quantum absorber - which can absorb any photon emitted by another system while maintaining entanglement with that system - has found diverse implications in open quantum system theory and quantum…

Quantum Physics · Physics 2025-03-06 Mankei Tsang

Exploring the noise spectrum impacting a qubit and extending its coherence duration are fundamental components of quantum technologies. In this study, we introduce parametric spectroscopy, a method that merges parametric modulation of a…

Quantum Physics · Physics 2025-03-10 Nir Gavrielov , Santiago Oviedo-Casado , Alex Retzker

In many physical problems it is not possible to find an exact solution. However, when some parameter in the problem is small, one can obtain an approximate solution by expanding in this parameter. This is the basis of perturbative methods,…

Mathematical Physics · Physics 2007-05-23 Paolo Amore

We show how to construct path integrals for quantum mechanical systems where the space of configurations is a general non-compact symmetric space. Associated with this path integral is a perturbation theory which respects the global…

High Energy Physics - Theory · Physics 2015-06-26 Noah Linden , Malcolm Perry

Band theory provides the foundation for understanding electronic structure in crystalline materials, but its reliance on exact translational symmetry limits its applicability to systems with defects, disorder, incommensurate modulations, or…

Materials Science · Physics 2026-05-08 Christopher A. Bairnsfather , Ralph M. Kaufmann , Terry A. Loring , Alexander Cerjan

In this article, we study the spectral properties of the perturbation of the generalized anharmonic oscillator. We consider a piecewise H\"older continuous perturbation and investigate how the H\"older constant can affect the eigenvalues.…

Functional Analysis · Mathematics 2019-02-13 Ksenia Fedosova , Medet Nursultanov

Continuous quantum measurement is the backbone of various methods in quantum control, quantum metrology, and quantum information. Here, we present a generalized formulation of dispersive measurement of a complex quantum systems. We describe…

Quantum Physics · Physics 2014-04-29 A. Shabani , J. Roden , K. B. Whaley

Dissipative quantum systems are sometimes phenomenologically described in terms of a non-hermitian hamiltonian $H$, with different left and right eigenvectors forming a bi-orthogonal basis. It is shown that the dynamics of waves in open…

Mathematical Physics · Physics 2007-05-23 P. T. Leung , W. -M. Suen , C. P. Sun , K. Young

This paper considers a Popov type approach to the problem of robust stability for a class of uncertain linear quantum systems subject to unknown perturbations in the system Hamiltonian. A general stability result is given for a general…

Quantum Physics · Physics 2013-03-08 Matthew R. James , Ian R. Petersen , Valery Ugrinovskii

In this third of a series of four articles, we continue the study of the representations of the hamiltonian dynamical transformations of systems of correlated quantized oscillators. By our use of generalized wave function solutions to…

High Energy Physics - Theory · Physics 2021-01-04 S. Maxson

The perturbative renormalization group(RG) equation is applied to resum divergent series of perturbative wave functions of quantum anharmonic oscillator. It is found that the resummed series gives the cumulant of the naive perturbation…

High Energy Physics - Theory · Physics 2009-09-25 Teiji Kunihiro

In this review, we summarize the main ideas of perturbative algebraic quantum field theory, which is a rigorous framework combining some of the Haag-Kastler axioms with perturbative methods involving formal power series. It allows for the…

Mathematical Physics · Physics 2025-12-17 Romeo Brunetti , Klaus Fredenhagen , Kasia Rejzner

A general program to show quantum-classical correspondence for bound conservative integrable and chaotic systems is described. The method is applied to integrable systems and the nature of the approach to the classical limit, the…

chao-dyn · Physics 2009-10-28 Joshua Wilkie , Paul Brumer

We construct a non-perturbative approach based on quantum averaging combined with resonant transformations to detect the resonances of a given Hamiltonian and to treat them. This approach, that generalizes the rotating-wave approximation,…

Quantum Physics · Physics 2007-05-23 M. Amniat-Talab , S. Guerin , H. R. Jauslin

Renormalization is a powerful technique in statistical physics to extract the large-scale behavior of interacting many-body models. These notes aim to give an introduction to perturbative methods that operate on the level of the stochastic…

Statistical Mechanics · Physics 2023-03-09 Nikos Papanikolaou , Thomas Speck

Variational perturbation theory is used to determine the decay rates of metastable states across a cubic barrier of arbitrary height. For high barriers, a variational resummation procedure is applied to the complex energy eigenvalues…

Quantum Physics · Physics 2016-08-15 H. Kleinert , I. Mustapic

We derive general evolution equations describing the ensemble-average quantum dynamics generated by disordered Hamiltonians. The disorder average affects the coherence of the evolution and can be accounted for by suitably tailored effective…

Quantum Physics · Physics 2016-08-30 Chahan Kropf , Clemens Gneiting , Andreas Buchleitner

A new approach to dissipative quantum systems modelled by a system plus environment Hamiltonian is presented. Using a continuous sequence of infinitesimal unitary transformations the small quantum system is decoupled from its…

Statistical Mechanics · Physics 2009-10-30 Stefan Kehrein , Andreas Mielke

We introduce a generalization of entanglement based on the idea that entanglement is relative to a distinguished subspace of observables rather than a distinguished subsystem decomposition. A pure quantum state is entangled relative to such…

Quantum Physics · Physics 2009-11-10 Howard Barnum , Emanuel Knill , Gerardo Ortiz , Rolando Somma , Lorenza Viola

The static and dynamic properties of many-body quantum systems are often well described by collective excitations, known as quasiparticles. Engineered quantum systems offer the opportunity to study such emergent phenomena in a precisely…

Quantum Physics · Physics 2015-09-09 P. Jurcevic , P. Hauke , C. Maier , C. Hempel , B. P. Lanyon , R. Blatt , C. F. Roos