%0 Journal Article
%A Rivas Vargas, Ángel
%A Luis Aina, Alfredo
%T Sub-Heisenberg estimation of non-random phase shifts
%D 2012
%@ 1367-2630
%U https://hdl.handle.net/20.500.14352/44589
%X We provide evidence that the uncertainty in detection of small and deterministic phase-shift deviations from a working point can be lower than the Heisenberg bound, for a fixed finite mean number of photons. We achieve that by exploiting nonlinearity of estimators and coherence with the vacuum.
%~