Mode-hopping mechanism generating colored noise in a magnetic tunnel junction based spin torque oscillator
Artikel i vetenskaplig tidskrift, 2014

The frequency noise spectrum of a magnetic tunnel junction based spin torque oscillator is examined where multiple modes and mode-hopping events are observed. The frequency noise spectrum is found to consist of both white noise and 1/f frequency noise. We find a systematic and similar dependence of both white noise and 1/f frequency noise on bias current and the relative angle between the reference and free layers, which changes the effective damping and hence the mode-hopping behavior in this system. The frequency at which the 1/f frequency noise changes to white noise increases as the free layer is aligned away from the anti-parallel orientation w.r.t the reference layer. These results indicate that the origin of 1/f frequency noise is related to mode-hopping, which produces both white noise as well as 1/f frequency noise similar to the case of ring lasers. (C) 2014 AIP Publishing LLC.

MODULATION

Physics

Applied

Författare

R. Sharma

Philipp Dürrenfeld

Göteborgs universitet

Ezio Iacocca

Göteborgs universitet

O. G. Heinonen

Johan Åkerman

Göteborgs universitet

Pranaba Muduli Kishor

Göteborgs universitet

Applied Physics Letters

0003-6951 (ISSN) 1077-3118 (eISSN)

Vol. 105

Ämneskategorier

Fysik

DOI

10.1063/1.4896634