Fair sampling perspective on an apparent violation of duality

• DOI: 10.1073/pnas.1400106111
• Publication Date: 2014-08-12T06:59:19Z
• Authors: Eliot Bolduc; Jonathan Leach; Filippo M. Miatto; Gerd Leuchs; Robert W. Boyd
• Keywords: Quantum Physics; 0103 physical sciences; FOS: Physical sciences; Quantum Physics (quant-ph); 01 natural sciences; Physics - Optics; Optics (physics.optics)

Significance In 2012, Menzel et al. reported on the results of a fundamental experiment raising questions regarding the simultaneous observation of wave-like and particle-like properties in a given quantum system. Whereas the general applicability of the duality principle to entangled subsystems is an open question, we bring the current understanding of the duality principle a step forward by theoretically deriving the strongest relations between the visibility of an interference pattern and the which-way information in a two-way interferometer such as Young’s double slit. This formalism successfully describes tests of duality where postselection on a subset of the interference pattern is applied. Our analysis even reconciles the surprising results of Menzel et al. with the duality principle in its standard form.