Magnetic skyrmionium is a donut-shaped spin texture with zero topological number $\left(Q\right)$ and has promising application in future spintronic devices. In this work, using micromagnetic simulation based on Landau-Lifshitz-Gilbert (LLG) equation, we report the generation of skyrmionium in an ultrathin magnetic nanoring in the presence of Dzyaloshinskii-Moriya interaction (DMI) and external magnetic field. By varying the DMI strength and outer diameter of a nanoring, the possibilities of creation of other skyrmion states (kπ states) are explored and we have reported the existence of 3π state and 4π state in nanoring for the first time. Also, we report that the transition of skyrmion state from kπ to (k-1)π occurs for a few millitesla (mT) magnetic fields in the out-of-plane configuration. Further, we have demonstrated the degeneration of skyrmionium $(Q=0)$ into an isolated skyrmion $(Q=\pm 1)$ and a pair of skyrmions $(Q=-2)$ in a nanoring of small dimension by applying an in-plane spin-polarized current. A complete study of the generation of skyrmionium and its topological stability is done by performing the micromagnetic simulation. Our results will provide guidelines for the design of spin-polarized current-controlled skyrmionium-skyrmion based spintronic memory and logic devices.

磁性skyrmionium是一种具有零拓扑数的甜甜圈状自旋纹理 $\left(问\right)$并在未来的自旋电子器件中具有广阔的应用前景。在这项工作中，我们使用基于 Landau-Lifshitz-Gilbert (LLG) 方程的微磁模拟，报告了在存在 Dzyaloshinskii-Moriya 相互作用 (DMI) 和外部磁场的情况下，在超薄磁性纳米环中生成了skyrmionium。通过改变纳米环的 DMI 强度和外径，探索了产生其他斯格明子态（kπ 态）的可能性，我们首次报道了纳米环中存在 3π 态和 4π 态。此外，我们报告说，在平面外配置中，几个毫特斯拉 (mT) 磁场会发生斯格明子状态从 kπ 到 (k-1)π 的转变。此外，我们已经证明了skyrmionium的退化$(问=0)$ 进入一个孤立的斯格明子 $(问=\pm 1)$ 和一对斯格明子 $(问=-2)$通过施加面内自旋极化电流在小尺寸的纳米环中。通过执行微磁模拟，对skyrmionium 的生成及其拓扑稳定性进行了完整的研究。我们的结果将为基于自旋电子存储器和逻辑器件的自旋极化电流控制skyrmionium-skyrmion 的设计提供指导。