After reviewing parity measurement based interferometry with twin-Fock states, which allows for super-sensitivity (Heisenberg-limited) and super-resolution, we consider interferometry with two different superpositions of twin-Fock states, namely two-mode squeezed vacuum states and pair coherent states. This study is motivated by the experimental challenge of producing twin-Fock states on opposite sides of a beam splitter. We find that input two-mode squeezed states, while allowing for Heisenberg-limited sensitivity, do not yield super-resolutions, whereas we that find both are possible with input pair coherent states.
@article{arxiv.1005.5038,
title = {Heisenberg-limited interferometry with pair coherent states and parity measurements},
author = {Christopher C. Gerry and Jihane Mimih},
journal= {arXiv preprint arXiv:1005.5038},
year = {2015}
}