Quantum network technology

Abstract

By generating a quantum entanglement among remote systems, which forms a quantum network, we can increase the size of the entire quantum system and perform an arbitrary quantum protocol. Such a quantum network enables quantum cryptography to realize ultimately secure communication and also realizes quantum teleportation and quantum computers. Quantum cryptography without using quantum entanglement has already entered the phase of practical use, and there are significant expectations for business uses. Research on elemental technologies for the upcoming entangled photon pair distribution and entanglement generation between matter and quantum systems has significantly advanced and attracts people’s attention. Recently, those quantum networks are called quantum internet, and the field tests are currently conducted in Europe, the U.S., and China. This article introduces a global trend regarding these quantum network technologies along with our research.