Spin-Torque Oscillator Based on Magnetic Tunnel Junction with a Perpendicularly Magnetized Free Layer and In-Plane Magnetized Polarizer

2013 ◽  
Vol 6 (10) ◽  
pp. 103003 ◽  
Author(s):  
Hitoshi Kubota ◽  
Kay Yakushiji ◽  
Akio Fukushima ◽  
Shingo Tamaru ◽  
Makoto Konoto ◽  
...  
Keyword(s):  
Tunnel Junction ◽  
Magnetic Tunnel Junction ◽  
Spin Torque ◽  
Free Layer

scholarly journals Magnetization Dynamics in a Perpendicular Anisotropy Free Layer under a Spin Torque Effect with Crossed Polarization

2020 ◽  
Vol 25 (1) ◽  
pp. 54
Author(s):  
Nafeesa Rahman ◽  
Rachid Sbiaa
Keyword(s):  
Tunnel Junction ◽  
Magnetic Tunnel Junction ◽  
Film Plane ◽  
Spin Torque ◽  
Spin Angular Momentum ◽  
Perpendicular Anisotropy ◽  
Free Layer ◽  
Magnetization Dynamics ◽  
Magnetization Direction ◽  
Spin Polarized

The transfer of spin angular momentum from a spin polarized current provides an efficient way of reversing the magnetization direction of the free layer of the magnetic tunnel junction (MTJ), and while faster reversal will reduce the switching energy, this in turn will lead to low power consumption. In this work, we propose a design where a spin torque oscillator (STO) is integrated with a conventional magnetic tunnel junction (MTJ) which will assist in the ultrafast reversal of the magnetization of the free layer of the MTJ. The structure formed (MTJ stacked with STO), will have the free layer of the MTJ sandwiched between two spin polarizer layers, one with a fixed magnetization direction perpendicular to film plane (main static polarizer) and the other with an oscillatory magnetization (dynamic polarizer). The static polarizer is the fixed layer of the MTJ itself and the dynamic polarizer is the free layer of the STO.

Spin torque in uniform magnetization

2017 ◽  
Author(s):  
Y. Suzuki
Keyword(s):  
Barrier Layer ◽  
Tunnel Junction ◽  
Spin Current ◽  
Magnetic Tunnel Junction ◽  
Spin Torque ◽  
Free Layer ◽  
Nonmagnetic Metal ◽  
Uniform Magnetization ◽  
Spin Polarized ◽  
Ferromagnetic Layers

This chapter discusses the effects of a spin current injected into a uniformly magnetized ferromagnetic cell. The junction consists of two ferromagnetic layers separated by a nonmagnetic metal interlayer or insulating barrier layer. With a nonmagnetic metal interlayer, the junction is called a giant magnetoresistive nanopillar, and with an insulating barrier layer a magnetic-tunnel junction. When charge current is passed through this device, the electrons are first spin polarized by the fixed layer and spin-polarized current is then injected into the free layer through the nonmagnetic interlayer. This spin current interacts with the spins in the host material by an exchange interaction and exerts a torque. If the exerted torque is large enough, magnetization in the free layer is reversed or continuous precession is excited.

Spin torque diode effect of the magnetic tunnel junction with MnGa free layer

2018 ◽  
Vol 112 (26) ◽  
pp. 262408 ◽  
Author(s):  
Sumito Tsunegi ◽  
Kotaro Mizunuma ◽  
Kazuya Suzuki ◽  
Hiroshi Imamura ◽  
Shingo Tamaru ◽  
...  
Keyword(s):  
Tunnel Junction ◽  
Magnetic Tunnel Junction ◽  
Spin Torque ◽  
Free Layer

scholarly journals Voltage Controlled Domain Wall Motion based Neuron and Stochastic Magnetic Tunnel Junction Synapse for Neuromorphic Computing Applications

2021 ◽  
Author(s):  
Aijaz Lone ◽  
Selma Amara ◽  
Hossein Fariborzi
Keyword(s):  
Domain Wall ◽  
Tunnel Junction ◽  
Thermal Noise ◽  
Wall Motion ◽  
Magnetic Tunnel Junction ◽  
Domain Wall Motion ◽  
Spin Orbit ◽  
Free Layer ◽  
Digit Recognition ◽  
Transport Studies

The present work discusses the proposal of a spintronic neuromorphic system with spin orbit torque driven domain wall motion-based neuron and synapse. We propose a voltage-controlled magnetic anisotropy domain wall motion based magnetic tunnel junction neuron. We investigate how the electric field at the gate (pinning site), generated by the voltage signals from pre-neurons, modulates the domain wall motion, which reflects in the non-linear switching behaviour of neuron magnetization. For the implementation of synaptic weights, we propose 3-terminal MTJ with stochastic domain wall motion in the free layer. We incorporate intrinsic pinning effects by creating triangular notches on the sides of the free layer. The pinning of domain wall and intrinsic thermal noise of device lead to the stochastic behaviour of domain wall motion. The control of this stochasticity by the spin orbit torque is shown to realize the potentiation and depression of the synaptic weight. The micromagnetics and spin transport studies in synapse and neuron are carried out by developing a coupled micromagnetic Non-Equilibrium Green’s Function (<i>MuMag-NEGF</i>) model. The minimization of the writing current pulse width by leveraging the thermal noise and demagnetization energy is also presented. Finally, we discuss the implementation of digit recognition by the proposed system using a spike time dependent algorithm.

scholarly journals Bolometric Properties of a Spin-Torque Diode Based on a Magnetic Tunnel Junction

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
G. D. Demin ◽  
K. A. Zvezdin ◽  
A. F. Popkov
Keyword(s):  
Tunnel Junction ◽  
Magnetic Tunnel Junction ◽  
Nonuniform Heating ◽  
Spin Torque ◽  
Rectification Effect ◽  
Wide Range ◽  
Spin Polarized ◽  
Potential Applications ◽  
Dynamic Components ◽  
Bolometric Effect

Spin caloritronics opens up a wide range of potential applications, one of which can be the thermoelectric rectification of a microwave signal by spin-diode structures. The bolometric properties of a spin-torque diode based on a magnetic tunnel junction (MTJ) in the presence of a thermal gradient through a tunnel junction are discussed. Theoretical estimates of the static and dynamic components of the microwave sensitivity of the spin-torque diode, related to thermoelectric tunnel magneto-Seebeck effect and the thermal transfer of spin angular momentum in the MTJ under nonuniform heating, are presented. Despite the fact that the thermal contribution to the microwave sensitivity of the spin-torque diode is found to be relatively small in relation to the rectification effect related to the modulation of the MTJ resistance by a microwave spin-polarized current, nevertheless, the considered bolometric effect can be successfully utilized in some real-world microwave applications.

scholarly journals Isotropically coercive free layer integration in a magnetic tunnel junction for neuromorphic applications

2020 ◽  
Author(s):  
Marco Mansueto ◽  
Antoine Chavent ◽  
Ricardo Sousa ◽  
Liliana D. Buda-Prejbeanu ◽  
Ioan L. Prejbeanu ◽  
...  
Keyword(s):  
Tunnel Junction ◽  
Magnetic Tunnel Junction ◽  
Free Layer

Compensation of orange-peel coupling effect in magnetic tunnel junction free layer via shape engineering for nanomagnet logic applications

2014 ◽  
Vol 115 (17) ◽  
pp. 17B902 ◽  
Author(s):  
Faisal A. Shah ◽  
Vijay K. Sankar ◽  
Peng Li ◽  
Gyorgy Csaba ◽  
Eugene Chen ◽  
...  
Keyword(s):  
Tunnel Junction ◽  
Coupling Effect ◽  
Magnetic Tunnel Junction ◽  
Orange Peel ◽  
Free Layer ◽  
Nanomagnet Logic

Influence of dynamical dipolar coupling on spin-torque-induced excitations in a magnetic tunnel junction nanopillar

2012 ◽  
Vol 111 (7) ◽  
pp. 07C906 ◽  
Author(s):  
Kiwamu Kudo ◽  
Tazumi Nagasawa ◽  
Hirofumi Suto ◽  
Tao Yang ◽  
Koichi Mizushima ◽  
...  
Keyword(s):  
Tunnel Junction ◽  
Dipolar Coupling ◽  
Magnetic Tunnel Junction ◽  
Spin Torque
Sign in / Sign up

Export Citation Format

Share Document