Nanoparticle magnetization measurements by a high sensitive nano-superconducting quantum interference device
Nanoparticle magnetization measurements by a high sensitive nano-superconducting quantum interference device
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DOI：
10.1063/1.4751036
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发表时间：
2012-09
影响因子：
4
通讯作者：
Roberto Russo;C. Granata;E. Esposito;D. Peddis;C. Cannas;A. Vettoliere
中科院分区：
文献类型：
--
作者：
Roberto Russo;C. Granata;E. Esposito;D. Peddis;C. Cannas;A. Vettoliere
采用高灵敏度纳米超导量子干涉仪（nanoSQUID）作为磁通量-临界电流转换器，通过适当的反馈电路测量亚铁磁性氧化铁纳米颗粒的磁化强度。利用环路电感的不对称性，提高了SQUID的响应度。通过在nanoSQUID环的平面中施加偏振场来激发具有8 nm的平均直径的氧化铁纳米颗粒。在T = 4.2 K的纳米颗粒的磁化强度的场依赖性显示磁滞。磁弛豫测量的报告，并与使用商业测量系统获得的。
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 = 4.2 K shows magnetic hysteresis. Magnetic relaxation measurements are reported and compared with those obtained by using a commercial measurement system.