Complementarity in variable strength quantum non-demolition measurements
Marco Barbieri, M. E. Goggin, Marcelo Pereira de Almeida, B. P. Lanyon, Andrew G. White · New Journal of Physics · 2009
Using a linear optic quantum gate we perform a variable strength quantum non-demolition measurement, to elucidate the role of which-path knowledge in a complementarity experiment. Specifically, we demonstrate that the entanglement created by the measurement interaction prevents an exhaustive description in terms of complementary wave-like and particle-like behaviour of a single photon in an interferometer.