FePt nanoparticles as high resolution magnetic force microscope (MFM) probes

ORAL

Abstract

Current MFM probes are often fabricated by sputtering a magnetic thin film across the entirety of an atomic force microscope (AFM) cantilever, limiting their spatial imaging resolution to about 30nm. We report our progress on improving this resolution by using single crystal, high-coercivity ferromagnetic FePt nanoparticles as magnetic sensors for MFM. By attaching nanomagnets 5-10 nm in diameter to the end of a functionalized AFM tip, this technique has potential for an image resolution of under 10nm. We are attempting to characterize the magnetic properties of a single nanomagnet using a novel scanning SQUID susceptometer capable of raising the sample temperature well above the SQUID temperature, with a SQUID pickup loop diameter and sensor-sample spacing well below a micron.

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Authors

  • L. Qian

    Stanford University, Geballe Laboratory for Advanced Materials, Stanford University

  • Jaemin Kim

    Brown University

  • J. R. Kirtley

    Stanford University, Geballe Laboratory for Advanced Materials, Stanford University

  • B. Kalisky

    Stanford University, Geballe Laboratory for Advanced Materials, Stanford University

  • Shouheng Sun

    Brown University

  • Kathryn Moler

    Stanford University, Geballe Laboratory for Advanced Materials, Stanford University, Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California, 94305, USA