Delayed-choice test of quantum complementarity with interfering single photons.
We report an experimental test of quantum complementarity with single-photon pulses sent into a Mach-Zehnder interferometer with an output beam splitter of adjustable reflection coefficient R. In addition, the experiment is realized in Wheeler's delayed-choice regime. Each randomly set value of R allows us to observe interference with visibility V and to obtain incomplete which-path information characterized by the distinguishability parameter D. Measured values of V and D are found to fulfill the complementarity relation V2+D2 < or =1.
Jacques
Vincent
V
Laboratoire de Photonique Quantique et Moléculaire, Ecole Normale Supérieure de Cachan, UMR CNRS 8537, Cachan, France.
Wu
E
E
Grosshans
Frédéric
F
Treussart
François
F
Grangier
Philippe
P
Aspect
Alain
A
Roch
Jean-François
JF