Current-Biased Kinetic Inductance Detector for Neutrons

We succeeded in measuring a clear signal from a single neutron by using a solid state superconducting current biased kinetic inductance detector, which consists of a superconducting Nb meanderline and an enriched ¹⁰B neutron conversion layer. Our neutron detector is able to operate at temperatures much lower than T_c. A full width at half maximum of signal remains at a few tens ns, ensuring fast operation as a neutron detector. A time-dependent histogram for the pulsed neutron intensity is in good agreement with the prediction from a Monte-Carlo simulation. We convincingly conclude that our detector was successful in detecting pulsed neutrons produced from the beam line BL10 at J-PARC.