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Title: Micro-focused Brillouin light scattering study of the magnetization dynamics driven by Spin Hall effect in a transversely magnetized NiFe nanowire

We employed micro-focused Brillouin light scattering to study the amplification of the thermal spin wave eigenmodes by means of a pure spin current, generated by the spin-Hall effect, in a transversely magnetized Pt(4 nm)/NiFe(4 nm)/SiO{sub 2}(5 nm) layered nanowire with lateral dimensions 500 × 2750 nm{sup 2}. The frequency and the cross section of both the center (fundamental) and the edge spin wave modes have been measured as a function of the intensity of the injected dc electric current. The frequency of both modes exhibits a clear redshift while their cross section is greatly enhanced on increasing the intensity of the injected dc. A threshold-like behavior is observed for a value of the injected dc of 2.8 mA. Interestingly, an additional mode, localized in the central part of the nanowire, appears at higher frequency on increasing the intensity of the injected dc above the threshold value. Micromagnetic simulations were used to quantitatively reproduce the experimental results and to investigate the complex non-linear dynamics induced by the spin-Hall effect, including the modification of the spatial profile of the spin wave modes and the appearance of the extra mode above the threshold.
Authors:
;  [1] ; ;  [2] ; ; ;  [3] ; ;  [4] ;  [5]
  1. Dipartimento di Fisica e Geologia, Università di Perugia, Perugia (Italy)
  2. Istituto Officina dei Materiali del CNR (CNR-IOM), Unità di Perugia, c/o Dipartimento di Fisica e Geologia, Università di Perugia, Perugia (Italy)
  3. Institute for Chemical Research, Kyoto University, Kyoto (Japan)
  4. Department of Electronic Engineering, Industrial Chemistry and Engineering, University of Messina, Messina (Italy)
  5. Department of Electrical and Information Engineering, Politecnico of Bari, Bari (Italy)
Publication Date:
OSTI Identifier:
22410080
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 17; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AMPLIFICATION; BRILLOUIN EFFECT; ELECTRIC CURRENTS; HALL EFFECT; IRON ALLOYS; LIGHT SCATTERING; MAGNETIZATION; NANOWIRES; NICKEL ALLOYS; NONLINEAR PROBLEMS; RED SHIFT; SILICON OXIDES; SPIN; SPIN WAVES