Enhancement of microwave to optical spin-based quantum transduction via a magnon mode

This presentation focus on quantum transduction using rare-earth ions in solid state systems. We propose using magnetic materials with rare-earth dopants, harnessing the strong coupling between rare-earth spin transitions and magnons. We analyze this situation using a formalism similar to Ref. PRL 113, 203601 (2014). We find that hosting rare-earth elements within a magnet dramatically speeds up the transduction rate by more than two orders of magnitude, which gives several key benefits: potentially higher efficiency as it is less affected by device internal losses, higher fidelity operations with the superconducting qubits, and reduced device constraints. Finally, we discuss several routes for implementing this type of quantum transducer.