  Wave-particle duality is a typical example of Bohr's complementarity
principle that plays a significant role in quantum mechanics. Previous studies
used the visibility of an interference pattern to quantify the wave property
and used path information to quantify the particle property. However, coherence
is the core and basis of the interference phenomenon. If we could use coherence
to characterize the wave property, the understanding of wave-particle duality
would be strengthened. A recent theoretical work [Phys. Rev. Lett. 116, 160406
(2016)] found two relations between quantum coherence and path information.
Here, we demonstrate the new measure of wave-particle duality based on two
kinds of coherence measures quantitatively for the first time. The wave
property, quantified by the coherence in the l1-norm measure and the relative
entropy measure, can be obtained via tomography of the target state, which is
encoded in the path degree of freedom of the photons. The particle property,
quantified by the path information, can be obtained via the discrimination of
detector states, which is encoded in the polarization degree of freedom of the
photons. Our work may deepen people's understanding of coherence and provide a
new perspective regarding wave-particle duality.
