Showing papers by "Xiaolong Zou published in 2009"

Anisotropic magnetization reversal in 30 nm triangular FeNi dots

Abstract: We present the room temperature magnetization hysteresis loop measurements of a triangularly shaped Fe64Ni36 dot array with the feature size down to 30 nm using magneto-optical Kerr effect An in-plane anisotropic magnetization reversal and an enhanced coercivity have been observed in these magnetic dots In combining with micromagnetic calculations, we found that the magnetization process follows two steps, the rotation of the top corner and the switching of the bottom base, respectively, controlled by the nanometer scale local magnetic shape anisotropy, and the thermal activation is negligible even in this length scale

Preparing spin-polarized scanning tunneling microscope probes on capped carbon nanotubes by Fe doping: A first-principles study

Abstract: Our first-principles calculations indicate the possibility of preparing spin-polarized scanning tunneling microscopy (SP-STM) probes from Fe-doped capped carbon nanotubes (CNTs). The structural stability, magnetic moment, and electronic property of hybrid systems are found to depend on the Fe adsorption site, which is attributed to the hybridization between Fe 3d and C 2p orbitals. The CNTs with Fe atoms adsorbed at the tip-top are demonstrated to be promising candidates for the SP-STM probe, with a high spin polarization leading to a completely spin-polarized current at lower voltages. In contrast, the CNTs encapsulating Fe atom are basically nonmagnetic, and thus useless for the SP-STM probe application in nature.