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Related papers: Time-dependent Decoherence-Free Subspace

200 papers

We consider N identical oscillators coupled to a single environment and show that the conditions for the existence of decoherence free subspaces are degeneracy of the oscillator frequencies and separability of the coupling with the…

Quantum Physics · Physics 2007-05-23 K. M. Fonseca Romero , S. G. Mokarzel , M. C. Nemes

This paper investigates the relationship between subsystems and time in a closed nonrelativistic system of interacting bosons and fermions. It is possible to write any state vector in such a system as an unentangled tensor product of…

Quantum Physics · Physics 2016-09-20 Bradley A. Foreman

Time-dependent density functional theory (TDDFT) is rapidly emerging as a premier method for solving dynamical many-body problems in physics and chemistry. The mathematical foundations of TDDFT are established through the formal existence…

Quantum Physics · Physics 2014-08-22 J. D. Whitfield , M. -H. Yung , D. G. Tempel , S. Boixo , A. Aspuru-Guzik

The general expectation that, in principle, time-dependent density functional theory (TDDFT) be an exact formulation of the time-evolution of an interacting N-electron system is critically reexamined. It is demonstrated that the previous…

Other Condensed Matter · Physics 2007-08-13 J. Schirmer , A. Dreuw

Coherence in an open quantum system is degraded through its interaction with a bath. This decoherence can be avoided by restricting the dynamics of the system to special decoherence-free subspaces. These subspaces are usually constructed…

Quantum Physics · Physics 2016-09-08 Daniel A. Lidar , Dave Bacon , Julia Kempe , K. B. Whaley

Adiabatic approximations in time-dependent density functional theory (TDDFT) will in general yield unphysical time-dependent shifts in the resonance positions of a system driven far from its ground-state. This spurious time-dependence is…

Chemical Physics · Physics 2016-08-24 Kai Luo , Johanna I. Fuks , Neepa T. Maitra

This paper introduces a spectral analysis of time-seires data derived from real-time time-dependent density functional theory (TDDFT) using Singular Spectrum Analysis (SSA). TDDFT is a robust method for obtaining molecular excited states…

Computational Physics · Physics 2025-10-02 Naoki Tani , Satoru S. Kano , Yasunari Zempo

Orthogonal time frequency space (OTFS) modulation is a two-dimensional signaling technique that has recently emerged in the literature to tackle the time-varying (TV) wireless channels. OTFS deploys the Doppler-delay plane to multiplex the…

Information Theory · Computer Science 2017-10-03 Arman Farhang , Ahmad RezazadehReyhani , Linda E. Doyle , Behrouz Farhang-Boroujeny

The main motivation of this article is to derive sufficient conditions for dynamical stability of periodically driven quantum systems described by a Hamiltonian H(t), i.e., conditions under which it holds sup_{t in R} | (psi(t),H(t) psi(t))…

Mathematical Physics · Physics 2009-11-13 Pierre Duclos , Eric Soccorsi , Pavel Stovicek , Michel Vittot

We investigate the notion of finite time stability for tempered fractional systems (TFSs) with time delays and variable coefficients. Then, we examine some sufficient conditions that allow concluding the TFSs stability in a finite time…

Optimization and Control · Mathematics 2023-11-20 Hanaa Zitane , Delfim F. M. Torres

Orthogonal Time Frequency Space (OTFS) is a novel modulation scheme designed in the Doppler-delay domain to fully exploit time and frequency diversity of general time-varying channels. In this paper, we present a novel discrete-time…

Information Theory · Computer Science 2017-10-24 Ahmad RezazadehReyhani , Arman Farhang , Mingyue Ji , Rong Rong Chen , Behrouz Farhang-Boroujeny

Time-dependent spin density functional theory (TD-SDFT) allows the theoretical description of spin and magnetization dynamics in electronic systems from first quantum mechanical principles. TD-SDFT accounts for electronic interaction…

Materials Science · Physics 2024-10-04 Jenna L. Bologa , Carsten A. Ullrich

We extend a perturbative Dyson-type treatment and discrete-symmetry constraints from the Schr\"{o}dinger and von Neumann equations to a dephasing Lindblad framework. This work develops further the odd-symmetric formulation involving dual…

Quantum Physics · Physics 2026-05-12 A. Y. Klimenko

In a number of physically relevant contexts, a quantum system interacting with a decohering environment is simultaneously subjected to time-dependent controls and its dynamics is thus described by a time-dependent Lindblad master equation.…

Quantum Physics · Physics 2026-02-19 Lasse H. Wolff , Daniel Malz , Rahul Trivedi

A new and thorough derivation of linear-response subsystem time-dependent density functional theory (TD-DFT) is presented and analyzed in detail. Two equivalent derivations are presented and naturally yield self-consistent subsystem TD-DFT…

Chemical Physics · Physics 2013-06-12 Michele Pavanello

We introduce a new class of out-of-equilibrium noninteracting topological phases, the topological space-time crystals. These are time-dependent quantum systems which do not have discrete spatial translation symmetries, but instead are…

Mesoscale and Nanoscale Physics · Physics 2022-05-06 Yang Peng

We describe the time-dependent restricted-active-space self-consistent-field (TD-RASSCF) method for a system of interacting bosons. We provide the theory of the method and discuss its numerical implementation. The method provides a general…

Quantum Physics · Physics 2017-04-28 Camille Lévêque , Lars Bojer Madsen

The time-dependent multiconfiguration self-consistent-field method based on the occupation-restricted multiple active space model is proposed (TD-ORMAS) for multielectron dynamics in intense laser fields. Extending the previously proposed…

Atomic Physics · Physics 2015-06-23 Takeshi Sato , Kenichi L. Ishikawa

We provide exact analytical solutions for a two dimensional explicitly time-dependent non-Hermitian quantum system. While the time-independent variant of the model studied is in the broken PT-symmetric phase for the entire range of the…

Quantum Physics · Physics 2019-06-05 Andreas Fring , Thomas Frith

The time-dependent restricted-active-space self-consistent-field (TD-RASSCF) method is formulated based on the TD variational principle. In analogy with the configuration-interaction singles (CIS), singles-and-doubles (CISD),…

Quantum Physics · Physics 2014-06-26 Haruhide Miyagi , Lars Bojer Madsen