Six-photon de Broglie wavelength and phase-measurement sensitivity improving upon the standard quantum limit
B. Liu, Z. Y. Ou · Physical Review A · 2010
Using only linear optics and projection measurement, we propose a simple multiphoton interference scheme for the demonstration of six-photon de Broglie wavelength, which leads to a $\mathrm{cos}6\ensuremath{\varphi}$ dependence on the single-photon phase $\ensuremath{\varphi}$. Although the scheme does not reach the Heisenberg limit in sensitivity for phase measurement, it improves upon the standard quantum limit with super-resolved sensitivity in phase measurement. We discuss possible experimental implementation with three pairs of photons from parametric down-conversion.