Related papers: Auto-oscillation threshold, narrow spectral lines,…
We discuss the coherence of magnetic oscillations in a magnetic tunnel junction-based spin-torque oscillator as a function of external field angle. Time-frequency analysis shows mode-hopping between distinct oscillator modes, which arises…
Strain-mediated voltage control of magnetization in piezoelectric/ferromagnetic systems is a promising mechanism to implement energy-efficient spintronic memory devices. Here, we demonstrate giant voltage manipulation of MgO magnetic tunnel…
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…
Thermal spin-transfer torque describes the manipulation of the magnetization by the application of a heat flow. The effect has been calculated theoretically by Jia et al. in 2011. It is found to require large temperature gradients in the…
Spin transfer in asymmetric Co/Cu/Co bilayer magnetic nanopillars junctions has been studied at low temperature as a function of free-layer thickness. The phase diagram for current-induced magnetic excitations has been determined for…
We report on the magnetic switching and backhopping effects due to spin-transfer-torque in magnetic tunnel junctions. Experimental data on the current-induced switching in junctions with MgO tunnel barrier reveal a random back-and-forth…
Non-equilibrium spin transport in a magnetic tunnel junction comprising a single magnetic layer in the presence of interfacial spin-orbit interaction (SOI) is studied theoretically. The interfacial SOI generates a spin torque of the form…
The critical current of the self-oscillation 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 (LLG) equation. We…
Perpendicular magnetic tunnel junctions based on MgO/CoFeB structures are of particular interest for magnetic random-access memories because of their excellent thermal stability, scaling potential, and power dissipation. However, the major…
We study spin-transfer-torque driven magnetization dynamics of a perpendicular magnetic tunnel junction (MTJ) nanopillar. Based on the combination of spin-torque ferromagnetic resonance and microwave spectroscopy techniques, we demonstrate…
Control of magnetism without using magnetic fields enables large-scale integration of spintronic devices for memory, computation and communication in the beyond-CMOS era. Mechanisms including spin torque transfer, spin Hall effect, and…
A theoretical study on how synchronization and resonance-like phenomena in superparamagnetic tunnel junctions can be driven by spin-transfer torques is presented. We examine the magnetization of a superparamagnetic free layer that reverses…
The antiferromagnets with the time-reversal symmetry broken magnetic structures possess a finite spin splitting in the momentum space, and may contribute to a realization of a finite tunnel magnetoresistance (TMR) effect even with magnets…
We report on a time-domain study of parametric synchronization in a magnetic tunnel junction based spin torque nano-oscillator (STNO). Time-domain measurements of the instantaneous frequency ($f_{i}$) of a parametrically synchronized STNO…
We propose a novel concept of obtaining oscillations with frequencies in very-high frequency (VHF) and ultra-high frequency (UHF) bands. A traditional spin torque nano-oscillator (STNO) consists of at least one pinned layer (PL) and one…
The possibility of quantum oscillations of the tunnel conductance and magnetoresistance induced by spin-wave excitations in a ferromagnet-ferromagnet-ferromagnet double barrier tunnel junction, when the magnetizations of the two side…
Self-oscillators are intriguing due to their ability to sustain periodic motion without periodic stimulus. They remain rare as achieving such behavior requires a balance of energy input, dissipation and non-linear feedback mechanism. Here,…
In this paper, a 3-terminal spin-transfer torque nano-oscillator (STNO) is studied using the concurrent spin injection of a spin-polarized tunneling current and a spin Hall current exciting the free layer into dynamic regimes beyond what is…
The thermal spin-transfer torque (TSTT) is an effect to switch the magnetic free layer in a magnetic tunnel junction by a temperature gradient only. We present ab initio calculations of the TSTT. In particular, we discuss the influence of…
We demonstrate field and current controlled magnetodynamics in nanocontact spin-torque nano-oscillators (STNOs) based on orthogonal magnetic tunnel junctions (MTJs). We systematically analyze the microwave properties (frequency $f$,…