Physics from the University of Chicago has demonstrated a new method of quantum communication based on entanglement of photons. This method of communication more reliable than used so far method of transmission of quantum information via traditional fiber optic channels. An article about the development published in the journal Physical Review Letters.
Quantum communication is a method of transmitting information using entangled quantum particles. This method of communication allows you to create a secure communication channel. Quantum communication it is almost impossible to intercept and read, but even if someone succeeds, he will leave behind obvious signs. However, the transfer of quantum information using photons via traditional channels, such as fiber optics, is complicated by the fact that the photons carrying the information, are often damaged or lost. It makes the signals weak or incoherent. Often, for accurate receipt of message you want to send it several times.
New method of quantum communication, proposed by researchers, is associated with the entanglement of photons. These particles can quantum-mechanically be confusing, and this confusion can persist at great distances. Thanks to quantum entanglement change the state of one particle cause a change of state of the other. The principle quantum communication uses this phenomenon to their advantage, by coding the information with him.
The authors of the new work wanted to find a way to transmit quantum information without losing it during transmission. To do this, scientists have developed a system that confused the two nodes communicate using microwave photons by means of a microwave cable. For this experiment, the researchers used microwave cable is about a meter long. Including turning off the system, quantum physicists have been able to confuse the two nodes and transfer information between them without the need of transmission of photons through the cable.
In the study, the researchers were able to transmit information between nodes at a distance of a meter, however, according to them, this distance can be increased. However, the system has limitations — it must be very cold, a few degrees above absolute zero. Although potentially the system can operate at room temperature instead of photons to use atoms. But while the technology of using cryogenic temperatures and photon shows better control over the transmission of information than its high temperature options. In the future, the researchers plan to entangle multiple photons together and create a more complicated bound state.
