Moreno Julian A, Kosel Jurgen
King Abdullah University of Science and Technology, Thuwal, 23955, Saudi Arabia.
Silicon Austria Labs, 9524, Villach, Austria.
Sci Rep. 2022 Nov 14;12(1):19510. doi: 10.1038/s41598-022-22623-0.
Multi-segmented cylindrical nanowires have properties that make them attractive for high-density, high-speed logic and memory applications. Investigations of the current-induced domain wall motion in cylindrical nanowires have, so far, typically been conducted with a background magnetic field. However, if performed at zero external field, they would be much more viable for their use in prospective electronic devices. Here, we present an all-magneto electrical method to consistently pin domain walls in multi-segmented nanowires and induce their de-pinning using current pulses. The experiments were conducted with compositionally modulated three-segmented nickel/cobalt/nickel and two-segmented cobalt/nickel nanowires of 190 and 150 nm diameter, respectively, where the soft/hard magnetic texture has been fairly studied. We find that for the 3 segmented nanowire, the domain wall can be de-pinned independent of the polarity of the pulse, while for the 2 segmented nanowire the domain wall de-pins only for one polarity. Applying current pulses of 1 × 10 A/m, we use a pulse width of 22 ns to estimate a lower boundary for the domain wall speed of 634.54 m/s in cobalt. We study the resistive heating effect from the DC measurement current to find a temperature increase of no more than 2 °C after more than 20 h of tests.
多段圆柱形纳米线具有一些特性，使其在高密度、高速逻辑和存储器应用方面颇具吸引力。到目前为止，圆柱形纳米线中电流诱导的畴壁运动研究通常是在背景磁场下进行的。然而，如果在零外场下进行，它们在未来电子器件中的应用将更具可行性。在此，我们提出一种全磁电方法，用于在多段纳米线中持续钉扎畴壁，并使用电流脉冲诱导其去钉扎。实验分别使用了直径为190纳米和150纳米的成分调制三段式镍/钴/镍和两段式钴/镍纳米线进行，其中软/硬磁织构已得到充分研究。我们发现，对于三段纳米线，畴壁可以独立于脉冲极性去钉扎，而对于两段纳米线，畴壁仅在一种极性下才去钉扎。施加1×10 A/m的电流脉冲，我们使用22纳秒的脉冲宽度来估计钴中畴壁速度的下限为634.54米/秒。我们通过直流测量电流研究了电阻加热效应，发现在超过20小时的测试后温度升高不超过2℃。
