论文标题
STM尖端的可切换分子功能化：从Yu-Shiba-Rusinov尖端到近代尖端
Switchable molecular functionalization of an STM tip: from a Yu-Shiba-Rusinov tip to a Kondo tip
论文作者
论文摘要
在这项工作中，我们构建并表征了扫描隧道显微镜（STM）的功能化超导（SC）NB尖端。用四喹啉甲甲烷分子（TCNQ）功能化尖端，该分子（TCNQ）接受尖端的电荷并产生磁矩。结果，在扫描隧道光谱法（STS）中，鉴定为Yu-Shiba-Rusinov（YSR）结合状态的尖锐，偏置对称的亚间隙状态出现在金属GR/IR/IR（111）样本的无特征状态下。尽管磁杂质与SC尖端的耦合状态取决于分子的初始吸收构型，但可以通过调谐尖端样本距离来可逆地控制超导尖端和带电的TCNQ分子之间的相互作用强度。从一个耦合方案到另一个耦合方案的受控过渡使我们能够验证两个竞争性多体效应的能量尺度之间的关系。用磁场突然从YSR绑定状态主导的尖端到近密歇根尖端，将NB尖端的SC状态突然开关。
In this work we fabricate and characterize a functionalized superconducting (SC) Nb tip of a scanning tunnelling microscope (STM). The tip is functionalized with a Tetracyanoquinodimethane molecule (TCNQ) that accepts charge from the tip and develops a magnetic moment. As a consequence, in scanning tunnelling spectroscopy (STS), sharp, bias symmetric sub-gap states identified as Yu-Shiba-Rusinov (YSR) bound states appear against the featureless density of states of a metallic gr/Ir(111) sample. Although the coupling regime of the magnetic impurity with the SC tip depends on the initial absorption configuration of the molecule, the interaction strength between the superconducting tip and the charged TCNQ molecule can be reversibly controlled by tuning the tip-sample distance. The controlled transition from one coupling regime to the other allows us to verify the relation between the energy scales of the two competing many-body effects for the functionalized tip. Quenching the SC state of the Nb tip with a magnetic field switches abruptly from a tip dominated by the YSR bound states to a Kondo tip.
