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Stronger Quantum Speed Limit for Mixed Quantum States
Shrobona Bagchi1, Dimpi Thakuria2,3, Arun Kumar Pati2,3
1Center for Quantum Information, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea.
Entropy (Basel, Switzerland)
|July 29, 2023
Summary
Researchers derived a new quantum speed limit for mixed quantum states using a stronger uncertainty relation. This optimized bound improves upon existing limits for quantum evolution speed.
Area of Science:
- Quantum Physics
- Quantum Information Theory
Background:
- Quantum speed limits define fundamental constraints on the rate of quantum evolution.
- Existing bounds are often less effective for mixed quantum states.
Purpose of the Study:
- To derive a tighter quantum speed limit for unitary evolution in mixed quantum states.
- To improve the precision of bounds on quantum dynamical processes.
Main Methods:
- Utilized the stronger uncertainty relation specifically for mixed quantum states.
- Optimized the derived bound by selecting appropriate Hermitian operators.
Main Results:
- Successfully derived a novel quantum speed limit for mixed quantum states.
- Demonstrated that the new bound offers superior performance compared to three existing bounds.
- Showcased optimization potential through illustrative examples.
Conclusions:
- The derived quantum speed limit provides a more accurate constraint for mixed quantum systems.
- The method offers a pathway to tighter bounds in quantum dynamics.
- This work advances the understanding of speed limits in realistic quantum states.
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