Implementation of quantum teleportation of photons across an air – water interface

Abstract

Since the theory of quantum mechanics brought about a revolution in physics nearly a century ago, various applications have emerged. In particular, the quantum properties of photons are being studied to provide a solution to some of the challenges faced by existing communication networks, such as security issues and energy efficiency. One of these properties is teleportation, via which information regarding the state of a photon, without its physical motion, can be transmitted across a classical channel. We report, perhaps for the first time, the teleportation of photons across a simulated air–water interface. An entangled pair of photons is generated from a mode-locked laser source, through spontaneous four-wave mixing (SFWM). One of the pair is sent wirelessly to an underwater receiver. Six States of Polarization are teleported sequentially, implementing active feed-forward operation, with the average fidelity of 96.7% surpassing the classical limit. This work is anticipated to lead to the establishment of a quantum communication link between two different media.