Write-error reduction in voltage-driven magnetization switching using a recording layer with low magnetic damping
Tatsuya Yamamoto, Tomohiro Ichinose, Takayuki Nozaki, Shingo Tamaru, Kay Yakushiji, Hitoshi Kubota, Shinji Yuasa
Abstract
We develop perpendicularly magnetized magnetic tunnel junctions consisting of a recording layer exhibiting a low magnetic damping to investigate the influence of magnetic damping on the write-error rate of voltage-driven magnetization switching. The effective magnetic damping is reduced to about one-third that of a conventional $\mathrm{Ta}$/$\mathrm{Co}\text{\ensuremath{-}}\mathrm{Fe}\text{\ensuremath{-}}\mathrm{B}$/$\mathrm{Mg}\mathrm{O}$ recording layer by eliminating the spin pumping effect. The low magnetic damping contributes to a 3-orders-of-magnitude reduction in the write-error rate for the longer write pulses, which is explained by the suppression of thermal fluctuation during the switching process. The low magnetic damping also enables a long period of magnetization precession to control the dynamics via the voltage-controlled magnetic anisotropy effect.