Related Experiment Video
Updated: May 9, 2026
05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Entanglement dynamics of two qubits coupled individually to Ohmic baths
Liwei Duan1, Hui Wang, Qing-Hu Chen
1Division of Materials Science, Nanyang Technological University, Singapore 639798, Singapore.
The Journal of Chemical Physics
|August 2, 2013
Summary
The Davydov D1 ansatz accurately simulates entanglement dynamics in two qubits interacting with two independent baths. It reveals finite-time disentanglement in strong coupling and oscillatory behavior with entanglement revival in intermediate coupling.
Area of Science:
- Quantum information science
- Condensed matter physics
- Quantum dynamics
Background:
- The spin-boson model describes quantum systems interacting with an environment.
- Accurate simulation of quantum entanglement dynamics is crucial for quantum technologies.
- The Davydov D1 ansatz offers an efficient and accurate trial state for time-dependent variational methods.
Purpose of the Study:
- To implement the Dirac-Frenkel time-dependent variational procedure with the Davydov D1 ansatz.
- To investigate the entanglement dynamics of two qubits coupled to two independent Ohmic baths.
- To explore quantum dynamics beyond the Born-Markov and rotating-wave approximations.
Main Methods:
- Utilized the Davydov D1 ansatz within the Dirac-Frenkel time-dependent variational procedure.
- Modeled two qubits interacting with two independent Ohmic spectral density baths.
- Avoided the Born-Markov and rotating-wave approximations for enhanced accuracy.
Main Results:
- Demonstrated finite-time disentanglement in the strong coupling regime.
- Observed oscillatory entanglement dynamics, including disappearance and revival, in the intermediate coupling regime.
- The Davydov D1 ansatz proved effective for studying complex quantum entanglement phenomena.
Conclusions:
- The Davydov D1 ansatz provides a robust framework for simulating quantum entanglement dynamics.
- The study highlights the rich entanglement behavior of two qubits in independent baths.
- Findings contribute to understanding quantum decoherence and entanglement in open quantum systems.
Related Concept Videos
01:23Atomic Nuclei: Nuclear Relaxation Processes
In the absence of an external magnetic field, nuclear spin states are degenerate and randomly oriented. When a magnetic field is applied, the spins begin to precess and orient themselves along (lower energy) or against (higher energy) the direction of the field. At equilibrium, a slight excess population of spins exists in the lower energy state. Because the direction of the magnetic field is fixed as the z-axis, the precessing magnetic moments are randomly oriented around the z-axis. This...
01:20Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
01:08NMR Spectroscopy: Spin–Spin Coupling
The spin state of an NMR-active nucleus can have a slight effect on its immediate electronic environment. This effect propagates through the intervening bonds and affects the electronic environments of NMR-active nuclei up to three bonds away; occasionally, even farther. This phenomenon is called spin–spin coupling or J-coupling. Coupling interactions are mutual and result in small changes in the absorption frequencies of both nuclei involved. While nuclei of the same element are involved in...
03:35Hybridization of Atomic Orbitals II
sp3d and sp3d 2 Hybridization
01:28Atomic Nuclei: Types of Nuclear Relaxation
Nuclear relaxation restores the equilibrium population imbalance and can occur via spin–lattice or spin–spin mechanisms, which are first-order exponential decay processes.
In spin–lattice or longitudinal relaxation, the excited spins exchange energy with the surrounding lattice as they return to the lower energy level. Among several mechanisms that contribute to spin–lattice relaxation, magnetic dipolar interactions are significant. Here, the excited nucleus transfers energy to a nearby...
In spin–lattice or longitudinal relaxation, the excited spins exchange energy with the surrounding lattice as they return to the lower energy level. Among several mechanisms that contribute to spin–lattice relaxation, magnetic dipolar interactions are significant. Here, the excited nucleus transfers energy to a nearby...
01:27¹H NMR: Long-Range Coupling
The coupling interactions of nuclei across four or more bonds are usually weak, with J values less than 1 Hz. While these are usually not observed in spectra, the presence of multiple bonds along the coupling pathway can result in observable long-range coupling.
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene π orbitals.
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene π orbitals.