Torque Magnetometry and Susceptometry using Split-Beam Optomechanical Nanocavities

ORAL

Abstract

A large number of sensitive magnetometry methods are limited to cryogenic operation. We present a highly sensitive torque magnetometer using a photonic crystal optomechanical split-beam nanocavity operating in air at room temperature. The chip-based magnetometer is proficient for probing both the net magnetization and AC susceptibility of individual magnetic microstructures. This is demonstrated through the observation of nanoscale Barkhausen transitions in the magnetic hysteresis of a permalloy thin-film element. Control of the vector direction of the radio frequency drive allows detection of accompanying AC susceptibility terms.

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Authors

  • Tayyaba Firdous

    Department of Physics and National Institute for Nanotechnology, University of Alberta, Canada

  • Nathanael Wu

    Department of Physics and Astronomy and Institute for Quantum Science and Technology, University of Calgary, Canada

  • Marcelo Wu

    Department of Physics and Astronomy and Institute for Quantum Science and Technology, University of Calgary, Canada

  • Fatemeh Fani Sani

    Department of Physics and National Institute for Nanotechnology, University of Alberta, Canada, Univ. of Alberta, Department of Physics and National Institute for Nanotechnology, Univ. of Alberta, Dept. of Physics and National Institute for Nanotechnology

  • Joseph Losby

    Department of Physics and National Institute for Nanotechnology, University of Alberta, Canada

  • Paul Barclay

    Department of Physics and Astronomy and Institute for Quantum Science and Technology, University of Calgary, Canada

  • Mark Freeman

    Department of Physics and National Institute for Nanotechnology, University of Alberta, Canada