Thomas Elliot – The Benefits of a Quantum Memory for Parsimonious Agents
The research team has found a way to increase the efficiency of photonic quantum memory up to 85% with a fidelity of more than 99%.
Quantum memory allows you to store and restore short-term states of single photons in quantum computers. Achieving high efficiency of such systems will still remain a serious problem, since it requires a perfectly matched photon-matter interface. The task is complicated by the fact that the energy of a single photon is small and can be easily lost in a noisy sea of diffused light background. For a long time, these problems did not allow to increase the efficiency of this type of memory by more than 50%..
Recently, a group of three Chinese universities managed to code a flying qubit to polarize a single photon and store it in rubidium atoms in a tiny hair-like space. At the same time, physicists cooled the alkali metal particles to almost absolute zero (0.00001 K) using lasers and a magnetic field. They also found a way to distinguish a single photon from background light noise..
Diagram of the experimental setup for single-photon quantum memory.
The development of the Chinese has brought the technology of the universal quantum computer one step closer to reality. Such memory devices can also be used in quantum networks and lay the foundation for the next generation of the Internet..
Although the system demonstrated in this work is designed for only one operation per qubit, it opens up the possibility for further technological developments in this direction..
We also previously reported about the development Russian physicists who suggested a new way to cool a quantum computer.
text: Ilya Bauer, photo: Hong Kong University of Science and Technology