Demid V. Sychev

Abstract The distinctive characteristics of light, such as high-speed and low-loss propagation, low crosstalk and low power consumption, along with the unique quantum properties of photons, make it most suitable for various applications in communications, high-resolution imaging, optical computing and quantum information technologies. One limiting factor, however, is the weak optical nonlinearity of conventional media, which poses challenges for controlling light at ultralow intensities.

M. Dabrowski, M. Mazelanik, M. Parniak, A. Leszczynski, M. Lipka, and W. Wasilewski, “Certification of high-dimensional entanglement and Einstein-Podolsky-Rosen steering with cold atomic quantum memory,” Phys. Rev. A 98, 042126 (2018). [Crossref] I. Marinković, A. Wallucks, R. Riedinger, S. Hong, M. Aspelmeyer, and S. Gröblacher, “Optomechanical bell test,” Phys. Rev. Lett. 121, 220404 (2018). [Crossref] X. Huang, E. Zeuthen, D. V. Vasilyev, Q. He, K. Hammerer, and E. S.

A simpler version of state Eq. (1) can be produced as sketched in Fig. 1a. We start with a weakly squeezed vacuum state with the squeezing parameter ζ = 0.18, generated in a horizontally polarized mode via degenerate parametric down-conversion. This state is an excellent approximation to the positive Schrödinger’s cat state \(\left| {{\mathrm{\Theta }}_ + } \right\rangle\) with the amplitude γ  = \(\sqrt \zeta\)6,12.