Magnetic properties such as coercivity, remanence and saturation magnetization will determine the area enclosed by the hysteresis loop of a magnetic material, which also represents magnetic heating. Nanowarming of cryopreserved organs is a new application for magnetic heating using nanoparticles. In this paper, isolated Ni MNW of different sizes and shapes are studied via micromagnetic simulation to explore the optimization of heating using individual MNW. Ellipsoidal MNWs with small (30nm) diameters turn out to be most promising in heating ability due to their large hysteresis area and their potential to distribute uniformly in an organ that is being heated. In addition to optimized heating, a special switching pattern of magnetic moment was also observed for cylindrical large (200nm) MNW. This special switching pattern can trigger applications such as quantum computing.
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Unlocking the decoding of unknown magnetic nanobarcode signatures
Magnetic nanowires (MNWs) rank among the most promising multifunctional magnetic nanomaterials for nanobarcoding applications owing to their safety, nontoxicity, and remote decoding using a single magnetic excitation source. Until recently, coercivity and saturation magnetization have been proposed as encoding parameters. Herein, backward remanence magnetization (BRM) is used to decode unknown remanence spectra of MNWs-based nanobarcodes. A simple and fast expectation algorithm is proposed to decode the unknown remanence spectra with a success rate of 86% even though the MNWs have similar coercivities, which cannot be accomplished by other decoding schemes. Our experimental approach and analytical analysis open a promising direction towards reliably decoding magnetic nanobarcodes to expand their capabilities for security and labeling applications.
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- Award ID(s):
- 1642268
- PAR ID:
- 10209707
- Date Published:
- Journal Name:
- Nanoscale Advances
- ISSN:
- 2516-0230
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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