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Time reversal and charge conjugation in an embedding quantum simulator.
Xiang Zhang1, Yangchao Shen1, Junhua Zhang1
1Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University, Beijing 100084, China.
Nature Communications
|August 5, 2015
Summary
Researchers experimentally simulated the complex conjugate, a previously impossible quantum operation. This breakthrough in quantum simulation enables new computational possibilities for complex problems.
Area of Science:
- Quantum Information Science
- Atomic Physics
- Computational Physics
Background:
- Quantum simulators promise to surpass classical computers for complex calculations.
- Implementing basic arithmetic operations like the complex conjugate is a significant challenge in quantum mechanics due to its linear nature.
Purpose of the Study:
- To experimentally demonstrate the quantum simulation of the complex conjugate operation.
- To explore 'unphysical' operations beyond standard unitary and dissipative quantum evolutions.
- To enable efficient computation of intractable quantities using quantum simulators.
Main Methods:
- Embedding quantum dynamics within the electronic multilevels of a Ytterbium-171 (¹⁷¹Yb⁺) ion.
- Implementing time reversal and charge conjugation, which are antiunitary symmetry operators.
- Performing operations without requiring tomographic knowledge of the quantum state.
Main Results:
- Successfully simulated the complex conjugate operation on a quantum system.
- Demonstrated the feasibility of antiunitary symmetry operations in quantum dynamics.
- Showcased a method applicable irrespective of system size.
Conclusions:
- Introduced a novel method to incorporate 'unphysical' operations into quantum simulation.
- Paved the way for efficient computation of complex quantities like entanglement monotones.
- Expanded the capabilities of quantum simulators for advanced computational tasks.
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