Nanomagnonic devices based on the spin-transfer torque

Abstract

Magnonics is based on signal transmission and processing by spin waves (or their quanta, called magnons) propagating in a magnetic medium. In the same way as nanoplasmonics makes use of metallic nanostructures to confine and guide optical-frequency plasmon-polaritons, nanomagnonics uses nanoscale magnetic waveguides to control the propagation of spin waves. Recent advances in the physics of nanomagnetism, such as the discovery of spin-transfer torque, have created possibilities for nanomagnonics. In particular, it was recently demonstrated that nanocontact spin-torque devices can radiate spin waves, serving as local nanoscale sources of signals for magnonic applications. However, the integration of spin-torque sources with nanoscale magnetic waveguides, which is necessary for the implementation of integrated spin-torque magnonic circuits, has not been achieved to date. Here, we suggest and experimentally demonstrate a new approach to this integration, utilizing dipolar field-induced magnonic nanowaveguides. The waveguides exhibit good spectral matching with spin-torque nano-oscillators and enable efficient directional transmission of spin waves. Our results provide a practical route for the implementation of integrated magnonic circuits utilizing spin transfer.

Traveling surface spin-wave resonance spectroscopy using surface acoustic waves

“…Dzyaloshinskii-Moriya interactions) [4][5][6][7][8][9][10] and on engineering new structures (e.g. magnonic crystals) for use in tailoring the propagation characteristics of spin waves [11][12][13][14][15][16][17][18] .…”

Propagating spin waves excited by spin-transfer torque: A combined electrical and optical study

“…This mode has been shown to consist of exchange-dominated spin waves (SWs) propagating radially away from the NC region at frequencies above the ferromagnetic resonance (FMR) frequency with a wavenumber inversely proportional to the NC diameter. The propagating nature of this mode lends itself to coupling NC-STOs to achieve better spectral features by synchronization [19][20][21][22][23], to perform computation [24,25], or to propagate information in magnonic devices [26,27].…”

Spin Torque Study of the Spin Hall Conductivity and Spin Diffusion Length in Platinum Thin Films with Varying Resistivity

“…The spin Hall effect (SHE) [1][2][3], in which a transverse spin current density SHE j is induced by a longitudinal charge current density e j and whose strength is characterized by the spin Hall ratio SH SHE (2 / ) / e e j j θ ≡ h , has recently drawn much attention because of its promise for spintronics applications [4][5][6][7][8][9][10][11][12][13]. Mechanisms which might give rise to the SHE [14,15] include the intrinsic SHE [1,16], side-jump scattering [17] and skew scattering [18].…”