Which-way identification by an asymmetrical double-slit experiment with monochromatic photons

Abstract

Recently, a laser beam asymmetrical double-slit experiment was proposed and performed, concerning ontological physical reality in quantum mechanics, under an assumption of single-photon interference. In the present study, by controlling better for saturation effects and upgrading the slit’s shape, we succeed in producing new interference samples with acceptable quality. Applying almost the same geometrical set-up, the present experiment makes the ”which-way” identification with higher experimental confidence. In the results, the ontological which-way effect observed in our recent experiment is well reconfirmed without any additional measurement of relative integral intensity.

Evidence of pair-correlation of which-way effects in the asymmetrical double-slit interference

“…1c. We have previously observed the effect with isolated single interference fringes produced only by I 2 -photons passing through the narrow slit [29,30]. For the present experiment, enlarging each spectrum, we manage to look for pair correlation of interference fringes at the two main minimum positions j = 7 and j = 12 of component spectra I 1 and I 2 , correspondingly.…”

“…1a shows the layout and the key elements of the present experiment with a red laser source and a screen with spectrum images being located at a far distance L from the slit diaphragm. The technical arrangement exacts one in our previous experiment [30]. Specifically, we took more pictures with enlarged sizes, adding 14 new spectra together with the 6 spectra in six former laser directions designated N 1 − N 6.…”

“…Other asymmetrical double-slit experiments with a laser beam in the far-field Fraunhofer condition [29,30] were performed, demonstrating an extreme contradictable correlation V 2 + D 2 = 2. In particular, it was suggested in [30] that the which-way phenomena would be observed simultaneously in interference missing orders of both slits. In this study, the experimental samples are performed according to a geometry similar to that in [30], i.e.…”

“…The asymmetrical double-slit interference was proposed in [27] and an experiment with electrons demonstrates in the near-field Fresnel condition a which-way identification of the two diffraction patterns with interference characterizing each of the slits [28]. Other asymmetrical double-slit experiments with a laser beam in the far-field Fraunhofer condition [29,30] were performed, demonstrating an extreme contradictable correlation V 2 + D 2 = 2. In particular, it was suggested in [30] that the which-way phenomena would be observed simultaneously in interference missing orders of both slits.…”

“…In particular, it was suggested in [30] that the which-way phenomena would be observed simultaneously in interference missing orders of both slits. In this study, the experimental samples are performed according to a geometry similar to that in [30], i.e. in the far-field Fraunhofer condition with single-photon approximation.…”