High-Fidelity quantum teleportation mediated by hole transfer in an acceptor-donor-radical molecular triad

Quantum teleportation transfers quantum states between nodes in a quantum network through entanglement distribution and subsequent Bell-state measurements. Here, we report electron spin teleportation through an unexplored hole-transfer mechanism within an ensemble of covalently linked acceptor-donor-stable radical (A-D-R^•) molecules. Photoexcitation of A after spin state preparation on R^• results in ultrafast hole transfer to produce an entangled pair ¹(A^•--D^•+). A subsequent spontaneous hole transfer ¹(A^•--¹[D^•+)-R^•] → A^•--D-R⁺ constitutes a Bell-state measurement, projecting the spin state initially prepared on R^• onto A^•-. Quantum state tomography using pulse electron paramagnetic resonance spectroscopy reveals successful teleportation. A fidelity of 98% is achieved due to high entanglement purity, small Larmor frequency mismatch between sender and receiver radicals, as well as minimized delay between state preparation and teleportation. These results represent an important step in developing molecular materials that can transfer information coherently between nanoscale quantum devices.