Microwave quantum teleportation

We demonstrate the successful realization of unconditional quantum teleportation in the microwave regime over the distance of 42 cm by exploiting two-mode squeezing and analog feedforward. We generate squeezed and feedforward signals in the GHz regime by using superconducting Josephson parametric amplifiers. We realize quantum teleportation of coherent states with fidelities exceeding the no-cloning limit, thus, proving the unconditional security of the protocol. Furthermore, our experiments reveal the influence of the feedforward gain and entanglement strength on the teleportation fidelity in the presence of finite noise and losses. In the end, we demonstrate that quantum microwave communication is feasible over macroscopic distances in the cryogenic environment. Our results enable future implementations of microwave quantum local area networks and distributed quantum computing with superconducting circuits.