Giant atoms boost quantum state transfer to over 99%

The team demonstrated that carefully engineered atoms, interacting strongly with light, can facilitate a reliable exchange of quantum information without active manipulation of the transmitting atom. The results establish giant atoms as a powerful platform for realizing high-fidelity quantum state transfer and demonstrate how time-dependent control can be encoded into the device design. Giant atoms offer a pathway to deterministic passive quantum state transfer, achieving fidelities exceeding 99% under optimized conditions. This level of precision stems from engineering the atoms’ interaction with light to create time-reversal-symmetric wavepackets, a feature typically requiring active control in other quantum transfer methods. The approach bypasses the need for active manipulation of the transmitting atom, simplifying the architecture of potential quantum networks. Theoretical work…