High-fidelity continuous-variable quantum teleportation toward multi-step quantum operations

TL;DR

This paper demonstrates high-fidelity continuous-variable quantum teleportation using improved squeezing techniques, achieving a fidelity of 0.83 and enabling multiple sequential teleportations for advanced quantum operations.

Contribution

The authors experimentally achieved the highest fidelity in CV quantum teleportation to date by adopting improved squeezing methods, facilitating multi-step quantum processes.

Findings

Teleportation fidelity of 0.83 achieved

Expected to perform approximately 5 sequential teleportations

Enhanced squeezing enables more complex quantum operations

Abstract

The progress in quantum operations of continuous-variable (CV) schemes can be reduced to that in CV quantum teleportation. The fidelity of quantum teleportation of an optical setup is limited by the finite degree of quantum correlation which can be prepared with a pair of finitely squeezed states. Reports of improvement of squeezing level have appeared recently, and we adopted the improved methods in our experimental system of quantum teleportation. As a result, we teleported a coherent state with a fidelity $F=0.83\pm 0.01$, which is better than any other figures reported to date. In this paper, we introduce a measure $n_{s}$, the number of teleportations expected to be carried out sequentially. Our result corresponds to $n_{s}$=5.0$\pm$0.4. It suggests that our improvement would enable us to proceed toward more advanced quantum operations involving multi-step quantum operations.