Spin-torque resonant expulsion of the vortex core for an efficient radiofrequency detection scheme

S. Jenkins (1) , R. Lebrun (1) , E. Grimaldi (1) , S. Tsunegi (1, 2) , P. Bortolotti (1) , H. Kubota (2) , K. Yakushiji (2) , A. Fukushima (2) , G. de Loubens (3) , O. Klein (4) , S. Yuasa (2) , V. Cros (1)

1 Laboratoire Albert Fert (ex-UMPhy Unité mixte de physique CNRS/Thales)
2 AIST - National Institute of Advanced Industrial Science and Technology
3 LNO - Laboratoire Nano-Magnétisme et Oxydes
4 SPINTEC - SPINtronique et TEchnologie des Composants

Spin-polarised radio-frequency currents, whose frequency is equal to that of the gyrotropic mode, will cause an excitation of the core of a magnetic vortex confined in a magnetic tunnel junction. When the excitation radius of the vortex core is greater than that of the junction radius, vortex core expulsion is observed, leading to a large change in resistance, as the layer enters a predominantly uniform magnetisation state. Unlike the conventional spin-torque diode effect, this highly tunable resonant effect will generate a voltage which does not decrease as a function of rf power, and has the potential to form the basis of a new generation of tunable nanoscale radio-frequency detectors.

Domaines: Physique [physics]; Matière Condensée [cond-mat]

S. Jenkins, R. Lebrun, E. Grimaldi, S. Tsunegi, P. Bortolotti, et al.. Spin-torque resonant expulsion of the vortex core for an efficient radiofrequency detection scheme. Nature Nanotechnology, 2016, 11 (4), pp.360 - 364. ⟨10.1038/nnano.2015.295⟩. ⟨cea-01484743⟩