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Measuring the Spin-Lattice Relaxation Magnetic Field Dependence of Hyperpolarized [1-13C]pyruvate
Published on: September 13, 2019
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Experimental Test of Entropic Noise-Disturbance Uncertainty Relations for Spin-1/2 Measurements
Georg Sulyok1, Stephan Sponar1, Bülent Demirel1
1Atominstitut, Vienna University of Technology, 1020 Vienna, Austria.
Physical Review Letters
|August 1, 2015
Summary
Researchers derived a tight quantum uncertainty relation for qubit measurements, experimentally confirming it by minimizing noise and disturbance in neutron spin experiments.
Area of Science:
- Quantum information science
- Quantum measurement theory
- Quantum uncertainty relations
Background:
- Information-theoretic definitions of noise and disturbance in quantum measurements were previously established.
- A state-independent noise-disturbance uncertainty relation was obtained in prior work.
Purpose of the Study:
- To derive a tight noise-disturbance uncertainty relation specifically for complementary qubit observables.
- To experimentally validate this derived relation.
Main Methods:
- Theoretical derivation of a tight uncertainty relation for qubit observables.
- Experimental implementation using successive projective measurements on a neutron's spin-1/2 system.
- Application of a correction procedure to minimize measurement disturbance.
Main Results:
- A tight noise-disturbance uncertainty relation for complementary qubit observables was successfully derived.
- Experimental results demonstrated saturation of this relation.
- The optimal correction procedure was identified to achieve the saturation.
Conclusions:
- The derived tight uncertainty relation for qubits is experimentally validated.
- Minimizing disturbance through optimal correction procedures is key to saturating quantum uncertainty relations.
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