Scientists from the Faculty of Physics have built an atomic memory for storing quantum information. It may prove useful in telecommunication. The paper on the topic was published in “Optics Express”.
The memory system which allows easy use of quantum information and is simple in structure was built by PhD candidates: Michał Dąbrowski and Radosław Chrapkiewicz, and Wojciech Wasilewski, PhD.
Quantum cryptography is already used in banks and the military. This encryption method guarantees full security. Until now, the processing of quantum information and its transmission on long distances were limited by lack of relevant memories. The memory created by the physicists from the University of Warsaw enables the quantum information to be recorded, stored and read.
– Until now, quantum memories required complicated laboratory equipment and a difficult process of freezing to extremely low temperatures, close to absolute zero. The atomic quantum memory that we have managed to build works in a much easier attainable temperature of several dozen degrees Centigrade – says Radosław Chrapkiewicz.
According to the physicists’ description, the main element of the memory is a glass chamber, 2.5 cm wide and 10 cm long, with rubidium-covered walls, filled with a noble gas. The use of laser impulses allows the information to be recorded and read.
For recording and reading quantum information, the physicists from the Faculty of Physics of the University of Warsaw used advanced methods of light filtering (patent pending) and an innovative camera of their own design.
– The retention time of quantum information stored in our memory is several to several dozen microseconds. Somebody could say: what sort of memory is that, lasting for such a short time? Still, you have to remember that everything depends on the application. In telecommunication, microseconds are enough to perform numerous attempts of transmitting quantum signals to the next transmission station – says Michał Dąbrowski.