Advanced Macro-Model with Pulse-Width Dependent Switching Characteristic for Spin Transfer Torque Based Magnetic-Tunnel-Junction Elements

Abstract

A stationary cold recombining helium plasma is generated in an arc-heated magnetically trapped expanding plasma jet that was developed in the authors' laboratory. The plasma can be generated very stably and spectroscopic analysis is accomplished with sufficient accuracy. Population densities of the He I levels whose principal quantum numbers are 3-6 and 7 9.8 3D, 9 3D levels are observed spectroscopically. When the plasma comes downstream, the electron temperature and density become low and population inversion is obtained between some level pairs, such as 4'S-3'P and 43P-33D. The degree of inversion is insufficient to be used for lasing. The electron temperature as found by Eoltzmann plots of the higher states drops to about 0.2 eV in the downstream expansion. The electmns are cooled by contact with cold residual gas. The magneticconfinement of the plasma jet is adequate to cause large population inversions without decreasing the electron density. The experimental results are explained in terms of a calculation based on a collisional radiative model including an optical thickness. The mechanisms of formation of DoDulation inversions are discussed in terms of atomic processes.

Multiferroic Memory: A Disruptive Technology or Future Technology?

“…Spin states of the magnetic materials are analogous to the polarization state of the ferroelectric materials or vice versa. Resistivity/conductivity of the magnetic system depends on the spin orientations, and their interaction with the nearest neighboring spins [45][46][47]. It means the switching of spin states either by external electrical field or magnetic field will provide different resistive states of the system.…”

Thermally consistent SPICE model for magnetic tunnel junction with multi-layered structures via interlayer interaction

“…In a static model, only the states of MTJ are described (according to bias condition, presence or absence of switched state) and then a resistance value is set. 4,5) In contrast, in a dynamic model, the time evolution of switching behavior is described along with the stationary characteristics of MTJ. Notably, the magnetization of the free layer of MTJ is represented as a function of time, and the resistance is determined using this magnetization.…”