Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:0810.0356 · Physical Review C

Dissipative quantum dynamics in low-energy collisions of complex nuclei

A. Díaz-Torres, David J. Hinde, M. Dasgupta, Gerard J Milburn, J. A. Tostevin

Published Dec 5, 2008• 55 citations
arXivHTMLPDF

Abstract

Model calculations that include the effects of irreversible, environmental couplings on top of a coupled-channels dynamical description of the collision of two complex nuclei are presented. The Liouville-von Neumann equation for the time evolution of the density matrix of a dissipative system is solved numerically providing a consistent transition from coherent to decoherent (and dissipative) dynamics during the collision. Quantum decoherence and dissipation are clearly manifested in the model calculations. Energy dissipation, due to the irreversible decay of giant-dipole vibrational states of the colliding nuclei, is shown to result in a hindrance of quantum tunneling and fusion.

DOI
10.1103/physrevc.78.064604

Related papers

Coupled-Channels Approach for Dissipative Quantum Dynamics in Near-Barrier Collisions

A. Díaz-Torres, David J. Hinde, M. Dasgupta +6 more

A novel quantum dynamical model based on the dissipative quantum dynamics of open quantum systems is presented. It allows the treatment of both deep‐inelastic processes and quantum tunneling (fusion) within a fully quantum mechanical coupled‐channels approach. Model calculations show the transition from pure state (coherent) to mixed state (decoherent and dissipative) dynamics during a near‐barrier nuclear collision. Energy dissipation, due to irreversible decay of giant‐dipole excitations of the interacting nuclei, results in hindrance of quantum tunneling.

arXiv:0811.1611•AIP conference proceedings•Jan 1, 2009•2 citations

Coupled-channels density-matrix approach to low-energy nuclear collision dynamics: A technique for quantifying quantum decoherence effects on reaction observables

A. Díaz-Torres

The coupled-channels density-matrix technique for nuclear reaction dynamics, which is based on the Liouville-von Neumann equation with Lindblad dissipative terms, is developed with the inclusion of full angular momentum couplings. It allows a quantitative study of the role and importance of quantum decoherence in nuclear scattering. Formulas of asymptotic observables that can reveal effects of quantum decoherence are given. A method for extracting energy-resolved scattering information from the time-dependent density matrix is introduced. As an example, model calculations are carried out for the low-energy collision of the $^{16}\mathrm{O}$ projectile on the $^{154}\mathrm{Sm}$ target.

arXiv:1010.3611•Physical Review C•Nov 29, 2010•25 citations

Coupled-Channels Density-Matrix Approach to Low-Energy Nuclear Reaction Dynamics

A. Díaz-Torres, Paraskevi Demetriou, Rauno Julin +1 more

Atomic nuclei are complex, quantum many‐body systems whose structure manifests itself through intrinsic quantum states associated with different excitation modes or degrees of freedom. Collective modes (vibration and/or rotation) dominate at low energy (near the ground‐state). The associated states are usually employed, within a truncated model space, as a basis in (coherent) coupled channels approaches to low‐energy reaction dynamics. However, excluded states can be essential, and their effects on the open (nuclear) system dynamics are usually treated through complex potentials. Is this a complete description of open system dynamics? Does it include effects of quantum decoherence? Can decoherence be manifested in reaction observables? In this contribution, I discuss these issues and the main ideas of a coupled‐channels density‐matrix approach that makes it possible to quantify the role and importance of quantum decoherence in low‐energy nuclear reaction dynamics. Topical applications, which refer to understanding the astrophysically important collision 12C+12C and achieving a unified quantum dynamical description of relevant reaction processes of weakly‐bound nuclei, are highlighted.

arXiv:1009.0520•AIP conference proceedings•Jan 1, 2011•0 citations

Quantum decoherence in low-energy nuclear reaction dynamics?

A. Díaz-Torres

Atomic nuclei are complex, quantum many-body systems whose structure manifests itself through intrinsic quantum states associated with different excitation modes or degrees of freedom.Collective modes (vibration and/or rotation) dominate at low energy (near the ground-state).The associated states are usually employed, within a truncated model space, as a basis in (coherent) coupled channels approaches to low-energy reaction dynamics.However, excluded non-collective states can be essential, and their effects on the open (nuclear) system dynamics are usually treated through complex potentials.Is this a complete description of open system dynamics?Does it include effects of quantum decoherence?Can decoherence be manifested in reaction observables?This paper discusses these issues and the main ideas of a coupled-channels density-matrix approach that makes it possible to quantify the role and importance of quantum decoherence in low-energy nuclear reaction dynamics.Some topical applications are highlighted.

Brazilian Workshop on Nuclear Physics (BWNP)•Mar 20, 2012•0 citations

Absence of decoherence in the complex-potential approach to nuclear scattering

A. Díaz-Torres

Time-dependent density-matrix propagation is used to demonstrate, in a schematic model of an open quantum system, that the complex potential approach and the Lindblad dissipative dynamics are not equivalent. While the former preserves coherence, it is destroyed in the Lindblad dissipative dynamics. Quantum decoherence is the key aspect that makes the difference between the two approaches, indicating that the complex potential model is inadequate for a consistent description of open quantum-system dynamics. It is suggested that quantum decoherence should always be explicitly included when modeling low-energy nuclear collision dynamics within a truncated model space of reaction channels.

arXiv:1005.0096•Physical Review C•Apr 30, 2010•19 citations

Coherence dynamics in low-energy nuclear fusion

Iain Lee, A. Díaz-Torres

Low-energy nuclear fusion reactions have been described using a dynamical coupled-channels density matrix method, based on the theory of open quantum systems. For the first time, this has been combined with an energy projection method, permitting the calculation of energy resolved fusion probabilities. The results are benchmarked against calculations using stationary Schrödinger dynamics and show excellent agreement. Calculations of entropy, energy dissipation and coherence were conducted, demonstrating the capability of this method. It is evident that the presence of quantum decoherence does not affect fusion probability. This framework provides a basis for quantum thermodynamic studies using thermal environments.

arXiv:2201.02232•Physics Letters B•Feb 18, 2022•10 citations
Model calculations that include the effects of irreversible, environmental couplings on top of a coupled-channels dynamical description of the collision of two complex nuclei are presented. The Liouville-von Neumann equation for the time evolution of the density matrix of a dissipative system is solved numerically providing a consistent transition from coherent to decoherent (and dissipative) dynamics during the collision. Quantum decoherence and dissipation are clearly manifested in the model calculations. Energy dissipation, due to the irreversible decay of giant-dipole vibrational states of the colliding nuclei, is shown to result in a hindrance of quantum tunneling and fusion.
A novel quantum dynamical model based on the dissipative quantum dynamics of open quantum systems is presented. It allows the treatment of both deep‐inelastic processes and quantum tunneling (fusion) within a fully quantum mechanical coupled‐channels approach. Model calculations show the transition from pure state (coherent) to mixed state (decoherent and dissipative) dynamics during a near‐barrier nuclear collision. Energy dissipation, due to irreversible decay of giant‐dipole excitations of the interacting nuclei, results in hindrance of quantum tunneling.
The coupled-channels density-matrix technique for nuclear reaction dynamics, which is based on the Liouville-von Neumann equation with Lindblad dissipative terms, is developed with the inclusion of full angular momentum couplings. It allows a quantitative study of the role and importance of quantum decoherence in nuclear scattering. Formulas of asymptotic observables that can reveal effects of quantum decoherence are given. A method for extracting energy-resolved scattering information from the time-dependent density matrix is introduced. As an example, model calculations are carried out for the low-energy collision of the 16O^{16}\mathrm{O}16O projectile on the 154Sm^{154}\mathrm{Sm}154Sm target.
Atomic nuclei are complex, quantum many‐body systems whose structure manifests itself through intrinsic quantum states associated with different excitation modes or degrees of freedom. Collective modes (vibration and/or rotation) dominate at low energy (near the ground‐state). The associated states are usually employed, within a truncated model space, as a basis in (coherent) coupled channels approaches to low‐energy reaction dynamics. However, excluded states can be essential, and their effects on the open (nuclear) system dynamics are usually treated through complex potentials. Is this a complete description of open system dynamics? Does it include effects of quantum decoherence? Can decoherence be manifested in reaction observables? In this contribution, I discuss these issues and the main ideas of a coupled‐channels density‐matrix approach that makes it possible to quantify the role and importance of quantum decoherence in low‐energy nuclear reaction dynamics. Topical applications, which refer to understanding the astrophysically important collision 12C+12C and achieving a unified quantum dynamical description of relevant reaction processes of weakly‐bound nuclei, are highlighted.
Atomic nuclei are complex, quantum many-body systems whose structure manifests itself through intrinsic quantum states associated with different excitation modes or degrees of freedom.Collective modes (vibration and/or rotation) dominate at low energy (near the ground-state).The associated states are usually employed, within a truncated model space, as a basis in (coherent) coupled channels approaches to low-energy reaction dynamics.However, excluded non-collective states can be essential, and their effects on the open (nuclear) system dynamics are usually treated through complex potentials.Is this a complete description of open system dynamics?Does it include effects of quantum decoherence?Can decoherence be manifested in reaction observables?This paper discusses these issues and the main ideas of a coupled-channels density-matrix approach that makes it possible to quantify the role and importance of quantum decoherence in low-energy nuclear reaction dynamics.Some topical applications are highlighted.
Time-dependent density-matrix propagation is used to demonstrate, in a schematic model of an open quantum system, that the complex potential approach and the Lindblad dissipative dynamics are not equivalent. While the former preserves coherence, it is destroyed in the Lindblad dissipative dynamics. Quantum decoherence is the key aspect that makes the difference between the two approaches, indicating that the complex potential model is inadequate for a consistent description of open quantum-system dynamics. It is suggested that quantum decoherence should always be explicitly included when modeling low-energy nuclear collision dynamics within a truncated model space of reaction channels.
Low-energy nuclear fusion reactions have been described using a dynamical coupled-channels density matrix method, based on the theory of open quantum systems. For the first time, this has been combined with an energy projection method, permitting the calculation of energy resolved fusion probabilities. The results are benchmarked against calculations using stationary Schrödinger dynamics and show excellent agreement. Calculations of entropy, energy dissipation and coherence were conducted, demonstrating the capability of this method. It is evident that the presence of quantum decoherence does not affect fusion probability. This framework provides a basis for quantum thermodynamic studies using thermal environments.