Abstract
We examine whether metrological resolution beyond coherent states is a nonclassical effect. We show that this is true for linear detection schemes but false for nonlinear schemes, and propose a very simple experimental setup to test it. We find a nonclassicality criterion derived from quantum Fisher information.
- Received 14 February 2010
DOI:https://doi.org/10.1103/PhysRevLett.105.010403
©2010 American Physical Society
