In 1983, Wigner outlined a modified Schrödinger--von-Neumann equation of motion for macroobjects, to describe their typical coupling to the environment. This equation has become a principal model of environmental decoherence which is beleived responsible for the emergence ofclassicality in macroscopic quantum systems. Typically, this happens gradually and asymptotically after a certain characteristic decoherence time. For the Wigner-function, however, one can prove that it evolves perfectly into a classical (non-negative) phase space distribution after a finite time of decoherence.In 1983, Wigner outlined a modified Schrödinger--von-Neumann equation of motion for macroobjects, to describe their typical coupling to the environment. This equation has become a principal model of environmental decoherence which is beleived responsible for the emergence ofclassicality in macroscopic quantum systems. Typically, this happens gradually and asymptotically after a certain characteristic decoherence time. For the Wigner-function, however, one can prove that it evolves perfectly into a classical (non-negative) phase space distribution after a finite time of decoherence.

arXiv:quant-ph/0212103Dec 17, 20021 citation

Environmental decoherence versus intrinsic decoherence

Philip C. E. Stamp

We review the difference between standard environmental decoherence and 'intrinsic decoherence', which is taken to be an ineluctable process of Nature. Environmental decoherence is typically modelled by spin bath or oscillator modes-we review some of the unanswered questions not captured by these models, and also the application of them to experiments. Finally, a sketch is given of a new theoretical approach to intrinsic decoherence, and this scheme is applied to the discussion of gravitational decoherence.We review the difference between standard environmental decoherence and 'intrinsic decoherence', which is taken to be an ineluctable process of Nature. Environmental decoherence is typically modelled by spin bath or oscillator modes-we review some of the unanswered questions not captured by these models, and also the application of them to experiments. Finally, a sketch is given of a new theoretical approach to intrinsic decoherence, and this scheme is applied to the discussion of gravitational decoherence.

arXiv:1205.5307Philosophical Transactions of the Royal Society A Mathematical Physical and Engineering SciencesAug 20, 201251 citations

The He Experiment Revealed

The MIT Press eBooksFeb 16, 20210 citations

System-environmental entanglement in critical spin systems under $ZZ$ -decoherence and its relation to strong and weak symmetriesSystem-environmental entanglement in critical spin systems under $ZZ$-decoherence and its relation to strong and weak symmetries

Yoshihito Kuno, Takahiro Orito, Ikuo Ichinose

Open quantum many-body systems exhibit nontrivial behavior under decoherence. In particular, system-environmental entanglement (SEE) is one of the efficient quantities for classifying mixed states subject to decoherence. In this work, we investigate the SEE of critical spin chains under nearest-neighbor ZZ Z Z -decoherence. We numerically show that the SEE exhibits a specific scaling law, in particular, its system-size-independent term (“ g g -function”) changes drastically its behavior in the vicinity of phase transition caused by decoherence. For the XXZ model in its gapless regime, a transition diagnosed by strong Rényi-2 correlations occurs as the strength of the decoherence increases. We determine the location of the phase transition by investigating the g g -function that exhibits a sharp change in the critical region of the transition. Furthermore, we find that the value of the SEE is twice that of the system under single-site Z Z -decoherence, which was recently studied by conformal field theory. From the viewpoint of Rényi-2 Shannon entropy, which is closely related to the SEE at the maximal decoherence, we clarify the origin of this g g -function behavior.Open quantum many-body systems exhibit nontrivial behavior under decoherence. In particular, system-environmental entanglement (SEE) is one of the efficient quantities for classifying mixed states subject to decoherence. In this work, we investigate the SEE of critical spin chains under nearest-neighbor ZZ Z Z -decoherence. We numerically show that the SEE exhibits a specific scaling law, in particular, its system-size-independent term (“ g g -function”) changes drastically its behavior in the vicinity of phase transition caused by decoherence. For the XXZ model in its gapless regime, a transition diagnosed by strong Rényi-2 correlations occurs as the strength of the decoherence increases. We determine the location of the phase transition by investigating the g g -function that exhibits a sharp change in the critical region of the transition. Furthermore, we find that the value of the SEE is twice that of the system under single-site Z Z -decoherence, which was recently studied by conformal field theory. From the viewpoint of Rényi-2 Shannon entropy, which is closely related to the SEE at the maximal decoherence, we clarify the origin of this g g -function behavior.

arXiv:2501.17481SciPost Physics CoreMar 4, 20261 citation

System-environmental entanglement in critical spin systems under

ZZ

-decoherence and its relation to strong and weak symmetries