Magnetization vortices and anomalous switching in patterned NiFeCo submicron arrays

Switching characteristics of 20-nm-thick NiFeCo submicron arrays are systematically studied by means of magnetometry, magnetic force microscopy, and micromagnetic simulation based on solution of the Landau–Lifshitz–Gilbert equation. A switching anomaly found in these structures could not be described by the magnetization coherent rotation model. Both experimental data and simulation results indicate that trapped magnetization vortices are responsible for the switching anomaly.

[1]  Jian-Gang Zhu,et al.  Switching field variation in patterned submicron magnetic film elements , 1997 .

[2]  Heinz Schmid,et al.  Hysteresis of submicron permalloy particulate arrays , 1988 .

[3]  J. Zhu,et al.  Micromagnetics of spin valve memory cells , 1996 .

[4]  Deconvolution of magnetic force images by Fourier analysis , 1992 .

[5]  Stephen Y. Chou,et al.  Nanolithographically defined magnetic structures and quantum magnetic disk (invited) , 1996 .

[6]  E. Wohlfarth,et al.  A mechanism of magnetic hysteresis in heterogeneous alloys , 1948, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[7]  Jian-Gang Zhu,et al.  End Domain States and Magnetization Reversal in Submicron Magnetic Structures , 1998, 7th Joint MMM-Intermag Conference. Abstracts (Cat. No.98CH36275).

[8]  J. Chapman,et al.  MICROMAGNETISM OF EPITAXIAL FE(001) ELEMENTS ON THE MESOSCALE , 1997 .

[9]  James M. Daughton,et al.  Size dependence of switching thresholds for pseudo spin valve MRAM cells , 1997 .

[10]  H. Goronkin,et al.  Switching Characteristics Of Submicron Dimension Permalloy Sandwich Films , 1997, 1997 IEEE International Magnetics Conference (INTERMAG'97).

[11]  S. Schultz,et al.  Observation of thermal switching of a single ferromagnetic particle , 1993 .

[12]  J. N. Chapman,et al.  Switching fields and magnetostatic interactions of thin film magnetic nanoelements , 1997 .

[13]  Effect of magnetocrystalline anisotropy in single-domain polycrystalline cobalt islands , 1995 .

[14]  Saied N. Tehrani,et al.  Submicron spin valve magnetoresistive random access memory cell , 1997 .