Counting magnetic flux quanta offers a new way to measure photon numbers

Researchers at AIST directly observed magnetic flux quanta generated in a superconductor by photon absorption and demonstrated a new photon-detection principle that identifies the number of photons from the number of these flux quanta.

• AIST directly observed flux quanta in a superconductor upon photon absorption
• Photon count is derived from the number of generated flux quanta
• The work proposes a new principle for photon-number-resolving detection