[13p-P8-1~46] 10 スピントロニクス・マグネティクス(ポスター)

▼ [13p-P8-2] Control and Manipulation of a Magnetic Skyrmionium in Nanostructures

Xichao ZHANG^1,2、〇Jing XIA^1,2、Yan ZHOU^1,2、Daowei WANG³、Xiaoxi LIU⁴、Weisheng ZHAO⁵、Motohiko EZAWA⁶ (1.Univ. of Hong Kong、2.Nanjing Univ.、3.Central South Univ.、4.Shinshu Univ.、5.Beihang Univ.、6.Univ. of Tokyo)

キーワード：Skyrmionium

Magnetic skyrmionium is a non-topological soliton with a doughnut-like spin texture in magnetic thin film, which can be phenomenologically viewed as a coalition of a magnetic skyrmion and a magnetic anti-skyrmion. Due to its zero topological number, that is, Q = 0, the skyrmionium has distinctive characteristics as compared to its topological skyrmion counterpart with Q = ±1. In this work, we systematically study the generation, manipulation and motion of a skyrmionium in nanostructures in the presence of a magnetic field or a spin current. We demonstrate the degeneration of a skyrmionium with Q = 0 into a skyrmion with Q = +1 or Q = -1 triggered by a magnetic field pulse in a nanodisk. We show the transformation of a skyrmionium with Q = 0 into two skyrmions with Q = +1 in a nanotrack. In addition, we investigate the motion dynamics of a skyrmionium as well as a bilayer-skyrmionium compared to that of a skyrmion. The velocity of a skyrmionium driven by vertical current can be faster than that of a skyrmion at a reasonable driving current density. The results have technological implications in the emerging field of skyrmionics.