Kinetic inductance magnetometer

• DOI: 10.1038/ncomms5872
• Publication Date: 2014-09-10T11:30:39Z
• Authors: Juho Luomahaara; Visa Vesterinen; Leif Grönberg; Juha Hassel
• Keywords: Physics - Instrumentation and Detectors; ta213; Condensed Matter - Superconductivity; FOS: Physical sciences; Instrumentation and Detectors (physics.ins-det); 02 engineering and technology; 01 natural sciences; 7. Clean energy; 3. Good health; Physical sciences; Applied physics; Superconductivity (cond-mat.supr-con); 0103 physical sciences; 0210 nano-technology

Ultrasensitive magnetic field detection is utilized in the fields of science, medicine and industry. We report on a novel magnetometer relying on the kinetic inductance of superconducting material. The kinetic inductance exhibits a non-linear response with respect to DC current, a fact that is exploited by applying magnetic flux through a superconducting loop to generate a shielding current and a change in the inductance of the loop. The magnetometer is arranged into a resonator, allowing readout through a transmission measurement that makes the device compatible with radio frequency multiplexing techniques. The device is fabricated using a single thin-film layer of NbN, simplifying the fabrication process compared to existing magnetometer technologies considerably. Our experimental data, supported by theory, demonstrates a magnetometer having potential to replace established technology in applications requiring ultra-high sensitivity.<br/>16 pages, 6 figures<br/>