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Dynamic transverse susceptibility in Au-Fe-Au "nano-onions"

H. Srikanth·E. E. Carpenter·C. J. O'Connor
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Abstract

A precision radio-frequency (RF) transverse modulation technique based on a resonant tunnel diode oscillator (TDO) has been used to study the dynamic susceptibility in novel ring-shaped single domain Fe nanoparticles synthesized using reverse-micelle chemistry. Hysteresis loops measured using a SQUID magnetometer indicate a large coercivity (Hc = 400Oe) below the blocking temperature (TB ~52K). The dynamic susceptibility shows remarkable consistency with the M-H data and exhibits peaks at characteristic anisotropy fields. Overall, these RF experiments are well suited to probe the magnetic anisotropy in nanophase materials.

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H. Srikanth, E. E. Carpenter, C. J. O'Connor. 1999-04-19. Dynamic transverse susceptibility in Au-Fe-Au "nano-onions". https://arxiv.org/abs/cond-mat/9904267

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