Balance Between Information Gain and Reversibility in Weak Measurement
Abstract
We derive a tight bound between the quality of estimating a quantum state by measurement and the success probability of undoing the measurement in arbitrary dimensional systems, which completely describes the tradeoff relation between the information gain and reversibility. In this formulation, it is clearly shown that the information extracted from a weak measurement is erased through the reversing process. Our result broadens the information-theoretic perspective on quantum measurement as well as provides a standard tool to characterize weak measurements and reversals.
- Publication:
-
Physical Review Letters
- Pub Date:
- October 2012
- DOI:
- 10.1103/PhysRevLett.109.150402
- arXiv:
- arXiv:1203.4909
- Bibcode:
- 2012PhRvL.109o0402C
- Keywords:
-
- 03.65.Ta;
- 03.67.Mn;
- Foundations of quantum mechanics;
- measurement theory;
- Entanglement production characterization and manipulation;
- Quantum Physics
- E-Print:
- 5 pages, final version