Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China.
Phys Chem Chem Phys. 2023 Feb 22;25(8):6079-6088. doi: 10.1039/d2cp05638k.
Magnetic clusters on an insulating substrate are potential candidates for spin-based quantum devices. Here we investigate the geometric, electronic, and magnetic structures of small Ti and Cr clusters, from dimers to pentamers, adsorbed on a single-layer hexagonal boron nitride (h-BN) sheet within the framework of density functional theory. The stable adsorption configurations of the Ti clusters and Cr clusters composed of the same number of atoms are found to be totally different from each other. The difference in their bonding mechanisms has been revealed by the density of states and the charge density difference of the corresponding adsorption systems. While chemical bonds are formed between the Ti atoms and the supporting sheet, the Cr clusters are found in the physisorption state on the substrate. In addition, it is shown that the h-BN sheet is energetically favorable for building three-dimensional Ti clusters. These findings support the use of h-BN as a suitable decoupling substrate for manipulation of quantum spin states in small transition metal (TM) clusters and fabrication of devices based on them.
在绝缘衬底上的磁性团簇是基于自旋的量子器件的潜在候选物。在这里，我们在密度泛函理论的框架内研究了吸附在单层六方氮化硼（h-BN）片上的小 Ti 和 Cr 团簇（从二聚体到五聚体）的几何、电子和磁结构。我们发现，由相同数量原子组成的 Ti 团簇和 Cr 团簇的稳定吸附构型彼此完全不同。通过相应吸附体系的态密度和电荷密度差揭示了它们在成键机制上的差异。在 Ti 原子与支撑片之间形成了化学键，而 Cr 团簇则被发现以物理吸附的状态存在于衬底上。此外，结果表明 h-BN 片对于构建三维 Ti 团簇在能量上是有利的。这些发现支持了使用 h-BN 作为合适的解耦衬底来操纵小过渡金属（TM）团簇中的量子自旋态，并制造基于它们的器件。
