Abstract—In these micro magnetic simulations, a finite-grid approximation was adopted, where a parallelepiped dot with perpendicular anisotropy was discretized into a two-dimensional array of a rectangular numerical grid. The grid size was chosen to be larger than the exchange length. The demagnetization fields are calculated by integrating those from apparent surface magnetic charges on boundary of each grid element. Thermally assisted magnetization reversal, where the switching ﬁeld is temporally reduced by heating the selected memory cell in the writing process, is considered in this simulation. Switching mode of thermally assisted magnetization reversal has been numerically investigated by solved Landau-Lifshift Gilbert equation for magnetic nano-dot with perpendicular anisotropy. This thermally scheme succeed to decrease reversal field down to hundreds Oe order. An oscilatory minimum field required for aligning magnetization along writing field direction was observed which can be attributed by an exchange length. This information gives the possibility to realize the high density of Magnetic Random Access Memories with small reversal field (up to hundreds Oersted order) in the reading and writing process.
Index Terms—Perpendicular anisotropy constant, threshold field, exchange length.
Nur Aji Wibowo is the final year of postgraduate student with the Sebelas Maret University, Indonesia.
(e-mail: email@example.com, firstname.lastname@example.org).
Budi Purnama is with the Sebelas Maret University, Indonesia. He is a lecturer in the Physics Department of Sebelas Maret University, Indonesia.(e-mail: email@example.com).
Cite: Nur Aji Wibowo, Budi Purnama, "Reversal Mode of Thermally Assisted Magnetization Reversal on Perpendicularly Magnetized Nano-Dot," International Journal of Engineering and Technology vol. 3, no. 4, pp. 384-387, 2011.