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Updated: May 17, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Generation of concurrence in a generalized central spin model with a three-spin interacting environment
Adithya A Vasista1, Anushka Agrawal1, Tanay Nag1
1BITS Pilani-Hyderabad Campus, Department of Physics, Telangana 500078, India.
Physical Review. E
|May 16, 2026
Summary
The three-spin interaction in an Ising model enhances bipartite entanglement in central spins. This interaction influences entanglement dynamics, showing a dip-revival structure and long-lived entanglement under specific conditions.
Area of Science:
- Quantum physics
- Condensed matter physics
Background:
- Bipartite entanglement is crucial for quantum information processing.
- Three-spin interactions can significantly alter system properties.
Purpose of the Study:
- To investigate the impact of a three-spin interacting term on bipartite entanglement.
- To explore entanglement generation in a generalized central spin model.
Main Methods:
- Studied the three-spin Ising model to analyze tripartite entanglement.
- Constructed a generalized central spin model with two central spins coupled to an environment.
- Investigated equilibrium and nonequilibrium dynamics of central spin entanglement.
Main Results:
- Three-spin interactions lead to tripartite entanglement in disordered regions.
- Concurrence exhibits a dip-revival structure in equilibrium critical environments.
- Nonequilibrium quenches show initial concurrence growth followed by decay, with maximal entanglement near multicritical points.
Conclusions:
- Three-spin interactions are beneficial for generating bipartite entanglement in central spins.
- Entanglement sustainability depends on the three-spin interaction strength and quench type.
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