Nanoparticle magnetization measurements by a high sensitive nano-superconducting quantum interference device

作者：Russo R; Granata C^*; Esposito E; Peddis D; Cannas C; Vettoliere A

来源：Applied Physics Letters, 2012, 101(12): 122601.

DOI：10.1063/1.4751036

A high sensitive nano superconducting quantum interference device (nanoSQUID) operating as a magnetic flux to critical current transducer with a suitable feedback circuit is employed to measure the magnetization of ferrimagnetic iron oxide nanoparticles. An improved SQUID responsivity has been obtained by using a loop inductance asymmetry. Iron oxide nanoparticles having a mean diameter of 8 nm have been excited by applying a polarizing field in the plane of the nanoSQUID loop. The field dependence of the nanoparticle magnetization at T = 4.2K shows magnetic hysteresis. Magnetic relaxation measurements are reported and compared with those obtained by using a commercial measurement system.

• 出版日期2012-9-17