Zhuang Qingfeng, Wang Xiaoli, Ye Lyuzhou, Yan YiJing, Zheng Xiao
Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
School of Chemistry and Chemical Engineering, Dezhou University, Dezhou, Shandong 253023, China.
J Phys Chem Lett. 2022 Mar 10;13(9):2094-2100. doi: 10.1021/acs.jpclett.2c00228. Epub 2022 Feb 28.
The spin-polarized scanning tunneling microscope (SP-STM) has served as a versatile tool for probing and manipulating the spintronic properties of atomic and molecular devices with high precision. The interplay between the local spin state and its surrounding magnetic environment significantly affects the transport behavior of the device. Particularly, in the contact regime, the strong hybridization between the SP-STM tip and the magnetic atom or molecule could give rise to unconventional Kondo resonance signatures in the differential conductance (d/d) spectra. This poses challenges for the simulation of a realistic tip control process. By combining the density functional theory and the hierarchical equations of motion methods, we achieve first-principles-based simulation of the control of a Ni-tip/Co/Cu(100) junction in both the tunneling and contact regimes. The calculated d/d spectra reproduce faithfully the experimental data. A cotunneling mechanism is proposed to elucidate the physical origin of the observed unconventional Kondo signatures.
自旋极化扫描隧道显微镜（SP-STM）已成为一种多功能工具，用于高精度探测和操纵原子及分子器件的自旋电子学特性。局部自旋态与其周围磁环境之间的相互作用显著影响器件的输运行为。特别是在接触区域，SP-STM针尖与磁性原子或分子之间的强杂化会在微分电导（d/d）谱中产生非常规的近藤共振特征。这给现实的针尖控制过程模拟带来了挑战。通过结合密度泛函理论和运动方程分层方法，我们实现了在隧穿和接触区域对Ni针尖/Co/Cu(100)结控制的基于第一性原理的模拟。计算得到的d/d谱忠实地再现了实验数据。提出了一种共隧穿机制来阐明所观察到的非常规近藤特征的物理起源。
