English
Related papers

Related papers: Spin-torque oscillator linewidth narrowing under c…

200 papers

The dynamics of a spin-torque-oscillator (STO) coupled with a nano-magnet through dipole-dipole interaction was studied numerically by using the macrospin model for the application of the STO as a read head sensor of hard disk drives. We…

Mesoscale and Nanoscale Physics · Physics 2013-01-29 H. Arai , T. Taniguchi , H. Imamura

The magnetization dynamics of spin torque oscillator (STO) consisting of a perpendicularly magnetized free layer and an in-plane magnetized pinned layer was studied by solving the Landau-Lifshitz-Gilbert equation. We derived the analytical…

Mesoscale and Nanoscale Physics · Physics 2014-02-07 Tomohiro Taniguchi , Hiroko Arai , Hitoshi Kubota , Hiroshi Imamura

We demonstrate a high-quality spin orbit torque nano-oscillator comprised of spin wave modes confined by the magnetic field by the strongly inhomogeneous dipole field of a nearby micromagnet. This approach enables variable spatial…

Mesoscale and Nanoscale Physics · Physics 2021-12-28 Chi Zhang , Inhee Lee , Yong Pu , Sergei A. Manuilov , Denis V. Pelekhov , P. Chris Hammel

Spin-torque oscillators are strong candidates as nano-scale microwave generators and detectors. However, because of large amplitude-phase coupling (non-linearity), phase noise is enhanced over other linear auto-oscillators. One way to…

Mesoscale and Nanoscale Physics · Physics 2017-04-05 Muftah Al-Mahdawi , Yusuke Toda , Yohei Shiokawa , Masashi Sahashi

Spin-torque nano-oscillators (STNO) are microwave auto-oscillators based on magnetic resonances having a nonlinear response with the oscillating amplitude, which provides them with a large frequency tunability including the possibility of…

Mesoscale and Nanoscale Physics · Physics 2020-11-25 Jan Albert , Ferran Macià , Joan Manel Hernàndez

The spin torque oscillator (STO), where the magnetization of the fixed layer is tilted out of the film plane, is capable of strong microwave signal generation in zero magnetic field. Through numerical simulations of the…

Materials Science · Physics 2008-04-29 Yan Zhou , C. L. Zha , S. Bonetti , J. Persson , Johan Akerman

Spin transfer driven excitations in magnetic nanostructures are characterized by a relatively large microwave emission linewidth (10 -100 MHz). Here we investigate the role of thermal fluctuations as well as of the non-linear…

Mesoscale and Nanoscale Physics · Physics 2015-06-03 J. F. Sierra , M. Quinsat , U. Ebels , D. Gusakova , I. Joumard , A. S. Jenkins , L. Buda-Prejbeanu , B. Dieny , M. C. Cyrille , A. Zeltser , J. A. Katine

We demonstrate the strong impact of the oscillator agility on the line broadening by studying spin transfer induced microwave emission in MgO-based tunnel junctions with current. The linewidth is almost not affected by decreasing the…

Materials Science · Physics 2015-05-13 B. Georges , J. Grollier , V. Cros , A. Fert , A. Fukushima , H. Kubota , K. Yakushijin , S. Yuasa , K. Ando

Stochastic dynamics of spin torque oscillators (STOs) can be described in terms of magnetization drift and diffusion over a current-dependent effective energy surface given by the Fokker-Planck equation. Here we present a method that…

Mesoscale and Nanoscale Physics · Physics 2015-06-15 Graham E. Rowlands , Jordan A. Katine , Juergen Langer , Jian Zhu , Ilya N. Krivorotov

The temperature dependence of a vortex-based nano-oscillator induced by spin transfer torque (STVO) in magnetic tunnel junctions (MTJ) is considered. We obtain emitted signals with large output power and good signal coherence. Due to the…

Materials Science · Physics 2015-06-03 P. Bortolotti , A. Dussaux , J. Grollier , V. Cros , A. Fukushima , H. Kubota , K. Yakushiji , S. Yuasa , K. Ando , A. Fert

The nonlinear frequency shift coefficient, which represents the strength of the transformation of amplitude fluctuations into phase fluctuations of an oscillator, is measured for MgO-based spin-torque oscillators by analyzing the current…

Materials Science · Physics 2015-05-13 Kiwamu Kudo , Tazumi Nagasawa , Rie Sato , Koichi Mizushima

We make measurements of power spectral density of the microwave voltage emitted by a spin torque nano-oscillator (STNO) and compare our experimental results to predictions of an analytic theory of a single-mode STNO dynamics by V. S.…

Other Condensed Matter · Physics 2009-11-13 C. Boone , J. A. Katine , J. R. Childress , J. Zhu , X. Cheng , I. N. Krivorotov

In the absence of an applied magnetic field, a spin-torque nano oscillator(STNO) with a tilted polarizer is studied using numerical simulation of the associated Landau-Lifshitz-Gilbert-Slonczewski equation. We find considerable enhancement…

Mesoscale and Nanoscale Physics · Physics 2020-05-20 R. Arun , 1 R. Gopal , V. K. Chandrasekar , M. Lakshmanan

Spin torque nano-oscillator has been extensively studied both theoretically and experimentally in recent decades due to its potential applications in future microwave communication technology and neuromorphic computing. In this work, we…

Mesoscale and Nanoscale Physics · Physics 2023-01-12 Xue Liang , Laichuan Shen , Xiangjun Xing , Yan Zhou

We investigate the spectral characteristics of spin torque oscillator (STO) excited by the spin Hall-induced spin current. We observe that the modest spin current injection triggers the conventional single peak oscillating behavior of STO.…

Mesoscale and Nanoscale Physics · Physics 2020-07-20 Shuichi Iwakiri , Satoshi Sugimoto , Yasuhiro Niimi , Kensuke Kobayashi , Yusuke Kozuka , Yukiko K. Takahashi , Shinya Kasai

The spin-transfer nano-oscillator (STNO) offers the possibility of using the transfer of spin angular momentum via spin-polarized currents to generate microwave signals. However, at present STNO microwave emission mainly relies on both…

When spin-orbit torques are measured using spin-torque ferromagnetic resonance (ST-FMR), two alternative ways of analyzing the results to extract the torque efficiencies -- lineshape analysis and analysis of the change in linewidth versus…

Mesoscale and Nanoscale Physics · Physics 2021-06-16 Saba Karimeddiny , Daniel C. Ralph

Spin-transfer torques in magnetic nanocontacts can lead to self-sustained magnetization oscillations that involve large-amplitude gyrotropic vortex motion. This dynamics consists of a steady state orbit around the nanocontact, which is made…

Materials Science · Physics 2010-07-23 Joo-Von Kim , Thibaut Devolder

We present an experimental study of the power spectrum of current-driven magnetization oscillations in MgO tunnel junctions under low bias. We find the existence of narrow spectral lines, down to 8 MHz in width at a frequency of 10.7 GHz,…

The lineshape in an auto-oscillator with a large nonlinear frequency shift in the presence of thermal noise is calculated. Near the generation threshold, this lineshape becomes strongly non-Lorentzian, broadened, and asymmetric. A…

Materials Science · Physics 2009-11-13 Joo-Von Kim , Q. Mistral , C. Chappert , V. S. Tiberkevich , A. N. Slavin