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Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
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Generation of entanglement in quantum parametric oscillators using phase control.
J C Gonzalez-Henao1, E Pugliese2, S Euzzor3
1Instituto de Física "Gleb Wataghin", Universidade Estadual de Campinas, Unicamp 13083-970, Campinas, São Paulo, Brazil.
Scientific Reports
|August 20, 2015
Summary
Researchers explored controlling quantum entanglement in coupled oscillators using an external sinusoidal perturbation. Entanglement occurs in unstable classical regions, allowing manipulation of quantum information via classical systems.
Area of Science:
- Quantum physics
- Quantum information science
- Condensed matter physics
Background:
- Quantum entanglement is crucial for quantum computing and cryptography.
- Environmental interactions (decoherence) lead to entanglement loss.
- Controlling entanglement in open quantum systems remains a challenge.
Purpose of the Study:
- To theoretically investigate the control of quantum entanglement in a system of two coupled oscillators.
- To explore the use of an external sinusoidal perturbation to manage entanglement.
- To understand the relationship between classical system stability and quantum entanglement.
Main Methods:
- Modeling a system of two coupled oscillators interacting with a common heat bath.
- Introducing time-dependent oscillation frequencies and external sinusoidal perturbations.
- Analyzing the conditions for entanglement generation and control.
Main Results:
- Quantum entanglement is achieved precisely in regions where the classical counterpart is unstable.
- Entanglement is not possible when the classical system is stable.
- Entanglement swapping between stable and unstable regions is controllable via the external perturbation's amplitude and phase.
- The entanglement rate correlates with the real part of the Floquet coefficient of the classical system.
Conclusions:
- External sinusoidal perturbations can effectively control quantum entanglement in coupled oscillators.
- Quantum information can be manipulated by operating on the classical system's stability.
- This work offers a novel approach to managing entanglement in open quantum systems.
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