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Dissipative Quantum Control of a Spin Chain.
Giovanna Morigi1, Jürgen Eschner2, Cecilia Cormick3
1Theoretische Physik, Universität des Saarlandes, D-66123 Saarbrücken, Germany.
Physical Review Letters
|November 28, 2015
Summary
Researchers developed a new protocol to prepare spin chains in complex many-body states using tailored nonunitary dynamics. This method utilizes spectral resolution, optimized pulses, and engineered dissipation for applications in quantum systems like trapped ions and Rydberg atoms.
Area of Science:
- Quantum physics
- Many-body systems
- Quantum information science
Background:
- Preparing specific quantum states in many-body systems is challenging.
- Nonunitary dynamics offer new pathways for state preparation.
Purpose of the Study:
- To present a protocol for preparing a spin chain in a generic many-body state.
- To demonstrate the application of tailored nonunitary dynamics for state preparation.
Main Methods:
- Utilizing spectral resolution of the target state.
- Employing optimized coherent pulses.
- Implementing engineered dissipation and feedback control.
Main Results:
- A protocol for preparing spin chains in generic many-body states was successfully outlined.
- An example demonstrated the preparation of an entangled antiferromagnetic state.
- The protocol's applicability to trapped ion and Rydberg atom chains was argued.
Conclusions:
- Tailored nonunitary dynamics provide a viable method for preparing complex quantum states.
- The proposed protocol is versatile and applicable to various quantum hardware platforms.
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