Quantum transducer and quantum transduction method

A quantum transduction method using a quantum transducer, the quantum transducer including

• a three-dimensional cavity resonator,
• a stack disposed in the three-dimensional cavity resonator, including a nonmagnetic first insulator film and a ferromagnetic or antiferromagnetic second insulator film that are stacked on each other, and having an interface between the first insulator film and the second insulator film,
• a magnetic field applicator configured to apply, to the stack, a magnetic field having a component perpendicular to the interface, and
• a microwave transceiver configured to transmit and receive a microwave to and from the stack, wherein
• the first insulator film and the second insulator film do not include a topological insulator, and
• the second insulator film has an easy axis of magnetization along a first axis that is perpendicular to the interface,
• the quantum transduction method comprising:
• emitting laser light to the stack from a direction inclined with respect to the first axis.