Direct test of the “quantum vampire’s” shadow absence with use of thermal light

Authors
K. G. Katamadze, E. V. Kovlakov, G. V. Avosopiants, and S. P. Kulik

Optics Letters, 44, 13, 3286-3289 (2019)

Abstract
The counterintuitive nature of quantum physics leads to a number of paradoxes. One of them is a “quantum vampire” effect [Fedorov et al., Optica 2, 112 (2015) ], which means that the photon annihilation in a part of a large beam does not change the shape of the beam profile (i.e., does not cast a shadow), but it may change the total beam intensity. Previously, this effect was demonstrated just in a simplified double-mode regime [Fedorov et al., Optica 2, 112 (2015), Katamadze et al., Optica 5, 723 (2018) ]. In this Letter, a direct test of shadow absence after the photon annihilation was performed using the thermal state of light at the input.