Abstract
Micromagnetic simulations for spin-transfer-induced magnetization dynamics in nanoscale low-resistance magnetic tunnel junctions (MTJs) are performed by using the modified Landau-Lifshitz equation in which a spin-transfer model for MTJs is included. Calculations show that critical switching current density (Jc) is about (4-8) × 106 A cm2, consistent with the experimental data, lower than the values found in metallic spin-valve nanopillars (typically in the order of ∼ 107 A cm2). A slight asymmetry of the critical current is observed in the magnetization switching loop, due to the asymmetry of the spin-torque factor. The switching time is related to the applied current, and our calculation results show that a longer switching time, 10-15 ns, is needed when the applied current density J is close to Jc, and it decreases down to 1 ns for J>2× 107 A cm2.
| Original language | English (US) |
|---|---|
| Article number | 08G515 |
| Journal | Journal of Applied Physics |
| Volume | 99 |
| Issue number | 8 |
| DOIs | |
| State | Published - 2006 |
Bibliographical note
Funding Information:This work was supported by the National Natural Science Foundation of China (Grant Nos. 10404019, 60490290, and 10374019), grants from the Science and Technology Committee of Shanghai (Grant Nos. 04D214001, 05PJ14016, and 05PJ14090).