Breakthrough in Quantum Memory: Long Coherence Times Achieved in Rare-Earth Crystal!

Researchers from Southern University of Science and Technology and collaborators have demonstrated 15-second spin coherence in a stoichiometric europium crystal, dissolving past constraints. This achievement allows for practical quantum memory without complex optical cavities. The innovative combination of ZEFOZ and CPMG techniques suppressed noise effectively. This finding could pave the way for advanced quantum repeater networks, crucial for future quantum communication.