Exponentially Enhanced Quantum Metrology
Abstract
We show that when a suitable entanglement-generating unitary operator depending on a parameter is applied on N qubits in parallel, a precision of the order of 2-N in estimating the parameter may be achieved. This exponentially improves the precision achievable in classical and in quantum nonentangling strategies.
- Publication:
-
Physical Review Letters
- Pub Date:
- June 2008
- DOI:
- arXiv:
- arXiv:quant-ph/0607152
- Bibcode:
- 2008PhRvL.100v0501R
- Keywords:
-
- 03.67.-a;
- 03.65.Ta;
- 06.20.Dk;
- 42.50.St;
- Quantum information;
- Foundations of quantum mechanics;
- measurement theory;
- Measurement and error theory;
- Nonclassical interferometry subwavelength lithography;
- Quantum Physics
- E-Print:
- 4 pages, 1 postscript figure