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Published on: May 30, 2014
Pure Gaussian state generation via dissipation: a quantum stochastic differential equation approach
1Department of Applied Physics and Physico-Informatics, Keio University, Hiyoshi, Kohoku, Yokohama, Japan. yamamoto@appi.keio.ac.jp
Summary
Researchers characterized Gaussian dissipative systems with unique pure steady states. This provides a method for engineering systems for quantum state transfer and clarifies the passive nature of nullifier dynamics.
Area of Science:
- Quantum physics
- Quantum optics
- Information theory
Background:
- Characterization of Gaussian dissipative systems is crucial for quantum technologies.
- Previous work established conditions for unique pure steady states.
- Engineering desired steady states, like cluster states, remains a challenge.
Purpose of the Study:
- To provide a quantum stochastic differential equation (QSDE) framework for analyzing Gaussian dissipative systems.
- To clarify the physical meaning of system characterization, specifically nullifier dynamics.
- To develop a practical method for implementing desired dissipative Gaussian systems for quantum state transfer.
Main Methods:
- Describing the system using quantum stochastic differential equations (QSDEs).
- Analyzing the nullifier dynamics of Gaussian systems.
- Utilizing the QSDE framework to design system implementation.
Main Results:
- Complete characterization of general Gaussian dissipative systems with unique pure steady states.
- Clarification that the nullifier dynamics of such systems are passive.
- A general method for implementing desired dissipative Gaussian systems for quantum state transfer.
Conclusions:
- The QSDE representation offers unique insights into Gaussian dissipative systems.
- The passivity of nullifier dynamics is a key feature of systems with unique pure steady states.
- This work enables the engineering of quantum systems for specific applications like state transfer.
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