Recent Advances in Nanocontact Spin-Torque Oscillators
Journal article, 2014
We present a comprehensive review of the most recent advances in nanocontact spin torque oscillators (NC-STOs). NC-STOs are highly tunable, with both applied magnetic field and dc, broadband microwave signal generators. As opposed to the nanopillar geometry, where the lateral cross section of the entire device has been confined to a typically <100 nm diameter, in NC-STOs, it is only the current injection site that has been laterally confined on top of an extended magnetic film stack. Three distinct material combinations will be discussed: 1) a Co/Cu/NiFe pseudospin valve (PSV) where both the Co and NiFe have a dominant in-plane anisotropy; 2) a Co/Cu/[Co/Ni](4) orthogonal PSV where the Co/Ni multilayer has a strong perpendicular anisotropy; and 3) a single NiFe layer with asymmetric non-magnetic Cu leads. We explore the rich and diverse magnetodynamic modes that can be generated in these three distinct sample geometries.
Magnetodynamics
ELECTRIC-CURRENT
PHASE-LOCKING
Engineering
MODULATION
MAGNETIC DROPLET SOLITONS
POLARIZED CURRENT
GENERATION
NANO-OSCILLATORS
Physics
Electrical & Electronic
DRIVEN
spin-torque oscillator (STO)
NANOMAGNET
Applied
spin waves (SWs)
spin-transfer torque (STT)
EXCITATION
Author
Randy K. Dumas
University of Gothenburg
S. R. Sani
S. M. Mohseni
Ezio Iacocca
University of Gothenburg
Y. Pogoryelov
Pranaba Muduli Kishor
University of Gothenburg
S. Chung
Philipp Dürrenfeld
University of Gothenburg
Johan Åkerman
University of Gothenburg
IEEE Transactions on Magnetics
0018-9464 (ISSN)
Vol. 50 6Subject Categories (SSIF 2011)
Physical Sciences
DOI
10.1109/tmag.2014.2305762