TY  - JOUR
A1  - Menzel, Ralf
A1  - Marx, Robert
A1  - Puhlmann, Dirk
A1  - Heuer, Axel
A1  - Schleich, Wolfgang
T1  - The photon
BT  - the role of its mode function in analyzing complementarity
JF  - Journal of the Optical Society of America : B, Optical physics
N2  - We investigate the role of the spatial mode function in a single-photon experiment designed to demonstrate the principle of complementarity. Our approach employs entangled photons created by spontaneous parametric downconversion from a pump mode in a TEM01 mode together with a double slit. Measuring the interference of the signal photons behind the double slit in coincidence with the entangled idler photons at different positions, we select signal photons of different mode functions. When the signal photons belong to the TEM01-like double-hump mode, we obtain almost perfect visibility of the interference fringes, and no "which slit" information is available in the idler photon detected before the slits. This result is remarkable because the entangled signal and idler photon pairs are created each time in only one of the two intensity humps. However, when we break the symmetry between the two maxima of the signal photon mode structure, the paths through the slits for these additional photons become distinguishable and the visibility vanishes. It is the mode function of the photons selected by the detection system that decides if interference or "which slit" information is accessible in the experiment.
Y1  - 2019
U6  - https://doi.org/10.1364/JOSAB.36.001668
SN  - 0740-3224
SN  - 1520-8540
VL  - 36
IS  - 6
SP  - 1668
EP  - 1675
PB  - Optical Society of America
CY  - Washington
ER  -