Design and validation of magnetic particle spectrometer for characterization of magnetic nanoparticle relaxation dynamics

TitleDesign and validation of magnetic particle spectrometer for characterization of magnetic nanoparticle relaxation dynamics
Publication TypeJournal Article
Year of Publication2017
AuthorsGarraud, N., R. Dhavalikar, L. Maldonado-Camargo, D. P. Arnold, and C. Rinaldi
JournalAIP Advances
Volume7
Issue5
Pagination056730
Date PublishedJan-05-2017
Abstract

The design and validation of a magnetic particle spectrometer (MPS) system used to study the linear and nonlinear behavior of magnetic nanoparticle suspensions is presented. The MPS characterizes the suspension dynamic response, both due to relaxation and saturation effects, which depends on the magnetic particles and their environment. The system applies sinusoidal excitation magnetic fields varying in amplitude and frequency and can be configured for linear measurements (1 mT at up to 120 kHz) and nonlinear measurements (50 mT at up to 24 kHz). Time-resolved data acquisition at up to 4 MS/s combined with hardware and software-based signal processing allows for wide-band measurements up to 50 harmonics in nonlinear mode. By cross-calibrating the instrument with a known sample, the instantaneous sample magnetization can be quantitatively reconstructed. Validation of the two MPS modes are performed for iron oxide and cobalt ferrite suspensions, exhibiting Néel and Brownian relaxation, respectively.

URLhttp://aip.scitation.org/doi/10.1063/1.4978003
DOI10.1063/1.4978003
Short TitleAIP Advances