Department of Physics, University of Arizona, Tucson, AZ, 85721, USA.
Department of Electrical & Computer Engineering, University of Minnesota, Minneapolis, MN, 55455, USA.
Sci Rep. 2023 Mar 1;13(1):3454. doi: 10.1038/s41598-023-29752-0.
Nb and its compounds are widely used in quantum computing due to their high superconducting transition temperatures and high critical fields. Devices that combine superconducting performance and spintronic non-volatility could deliver unique functionality. Here we report the study of magnetic tunnel junctions with Nb as the heavy metal layers. An interfacial perpendicular magnetic anisotropy energy density of 1.85 mJ/m was obtained in Nb/CoFeB/MgO heterostructures. The tunneling magnetoresistance was evaluated in junctions with different thickness combinations and different annealing conditions. An optimized magnetoresistance of 120% was obtained at room temperature, with a damping parameter of 0.011 determined by ferromagnetic resonance. In addition, spin-transfer torque switching has also been successfully observed in these junctions with a quasistatic switching current density of 7.3 [Formula: see text] A/cm.
由于其超导转变温度高和临界场强高，Nb 及其化合物在量子计算中得到了广泛应用。结合超导性能和自旋电子非易失性的器件可以提供独特的功能。在这里，我们报告了使用 Nb 作为重金属层的磁性隧道结的研究。在 Nb/CoFeB/MgO 异质结构中获得了 1.85 mJ/m 的界面垂直各向异性磁能密度。在不同厚度组合和不同退火条件的结中评估了隧道磁阻。在室温下获得了优化的 120%磁阻，通过铁磁共振确定了 0.011 的阻尼参数。此外，在这些结中还成功观察到了自旋转移扭矩切换，准静态切换电流密度为 7.3 [Formula: see text] A/cm。
