Optical Communication with invisible photon

Robert J. McEliece, Eugene R. Rodemich, A. L. Rubin

Muhammad Suhail Zubairy

It has always been a self-evident and obvious feature of any kind of communication that there should be an exchange of objects like photons or electrons between the sender and the receiver to convey any information. In this chapter a protocol is presented in which information is transmitted between a sender and receiver with no particles in the transmission channel. The basic building block of this counterfactual communication protocol, the Mach–Zehnder interferometer, is discussed. The concept of interaction-free measurement is also introduced.

Konrad Banaszek

Hatim Salih, Zheng-Hong Li, M. Al-Amri +1 more

It has long been assumed physical particles have to travel between two parties in empty space for exchanging information. However, by using the “chained” quantum Zeno effect, we show, in the ideal asymptotic limit, information can be transferred without any physical carriers.

Daniel F. Walls, Gerard J Milburn

Zheng-Hong Li, Muhammad Suhail Zubairy, M. Al-Amri

We propose a quantum secure group communication protocol for the purpose of sharing the same message among multiple authorized users. Our protocol can remove the need for key management that is needed for the quantum network built on quantum key distribution. Comparing with the secure quantum network based on BB84, we show our protocol is more efficient and securer. Particularly, in the security analysis, we introduce a new way of attack, i.e., the counterfactual quantum attack, which can steal information by "invisible" photons. This invisible photon can reveal a single-photon detector in the photon path without triggering the detector. Moreover, the photon can identify phase operations applied to itself, thereby stealing information. To defeat this counterfactual quantum attack, we propose a quantum multi-user authorization system. It allows us to precisely control the communication time so that the attack can not be completed in time.