Spin torque oscillations triggered by in-plane field. (7th January 2022)

• Record Type: Journal Article
• Authors: Arun, R; Gopal, R; Chandrasekar, V K; Lakshmanan, M
• Is Part Of: Journal of physics. Volume 34:Number 12(2022)
• Publication Date: 2022-01-07
• Subjects: nonlinear dynamics -- spintronics -- high-frequency oscillations -- spin transfer torque, magnetization dynamics, self-oscillation, frequency and power; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/ac452f
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: We study the dynamics of a spin torque nano oscillator that consists of parallelly magnetized free and pinned layers by numerically solving the associated Landau–Lifshitz–Gilbert–Slonczewski equation in the presence of a field-like torque. We observe that an in-plane magnetic field which is applied for a short interval of time ( < 1 ns) triggers the magnetization to exhibit self-oscillations from low energy initial magnetization state. Also, we confirm that the frequency of oscillations can be tuned over the range ∼25–∼72 GHz by current, even in the absence of field-like torque. We find the frequency enhancement up to 10 GHz by the presence of field-like torque. We determine the Q -factor for different frequencies and show that it increases with frequency. Our analysis with thermal noise confirms that the system is stable against thermal noise and the dynamics is not altered appreciably by it.