Sub-nanosecond time-resolved near-field scanning magneto-optical microscope.
We report on the development of a new magnetic microscope, time-resolved near-field scanning magneto-optical microscope, which combines a near-field scanning optical microscope and magneto-optical contrast. By taking advantage of the high temporal resolution of time-resolved Kerr microscope and the sub-wavelength spatial resolution of a near-field microscope, we achieved a temporal resolution of ∼50 ps and a spatial resolution of <100 nm. In order to demonstrate the spatiotemporal magnetic imaging capability of this microscope, the magnetic field pulse induced gyrotropic vortex dynamics occurring in 1 μm diameter, 20 nm thick CoFeB circular disks has been investigated. The microscope provides sub-wavelength resolution magnetic images of the gyrotropic motion of the vortex core at a resonance frequency of ∼240 MHz.
Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8P 5C2, Canada.
J
J
Rudge
Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8P 5C2, Canada.
H
H
Xu
Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8P 5C2, Canada.
J
J
Kolthammer
Department of Electrical and Computer Engineering, University of Alabama, Tuscaloosa, Alabama 35487, USA.
Y K
YK
Hong
Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8P 5C2, Canada.
B C
BC
Choi