学术文献库

Present-day quantum communication predominantly depends on trusted relays (e.g., quantum repeaters, low-Earth-orbit satellite) connected by optical fiber cables to transmit information. However, recent evidence supports a decades-old concept that quantum entanglement, harnessed by current quantum communication systems, does not necessarily rely on a physical relay medium. In modern quantum communication networks, this trusted relay infrastructure is (1) susceptible to security attacks, (2) limited by the channel capacity, (3) subject to decoherence loss, and (4) expensive to set up. The instantaneous and faster-than-light activities of quantum entanglement occurring in quantum communication have suggested guidance by some non-locality nature. On the contrary, neither ground nor space-relays have shown or been demonstrated to embody it. It is proposed in this paper that the non-locality nature of quantum theory governs quantum entanglement; elementary particles, components of a universal quantum body, can achieve remote entanglement regardless of a physical medium or spatial proximity. Evidence and theory supporting remote entanglement in superconducting quantum systems (entanglement fidelities for communication in particular) are presented. One such particle, the photon, representing a basic unit of quantum information, qubit $|ψ\rangle = α|0\rangle + β|1\rangle$, consists of real continuous values in complex numbers $(α, β)$ with infinite precision. These values $(α, β)$ can account for the distinctiveness of qubits and result in an identity $QuID$ that possibly supports remote entanglement. New approaches to medium-free secure quantum communication are suggested by running simulations and actual quantum computations on a quantum circuit.