Chen Peng, Wang Weihua, Lin Nian, Du Shengwang
Opt Express. 2014 Apr 7;22(7):8234-42. doi: 10.1364/OE.22.008234.
We demonstrate manipulation of photon emission efficiency in a tunneling gap by tuning the rates of elastic and inelastic electron tunneling processes with local electronic states. The artificial local electronic states are created by a scanning tunneling microscope tip on a CuN nanoisland grown on a Cu(100) surface at cryogenic temperature. These local electronic states can either enhance or suppress the excitation of tip-induced surface plasmon modes at specific bias voltages, and thus the induced photon emission rates. A theoretical model quantitatively analyzing inelastic and elastic tunneling processes associated with characteristic electronic states shows good agreement with experiments. We also show that tip-induced photon emission measurement can be used for probing the electronic states in the tunneling gap.
我们通过利用局部电子态来调节弹性和非弹性电子隧穿过程的速率，展示了对隧穿间隙中光子发射效率的操控。人工局部电子态是由低温下在Cu(100)表面生长的CuN纳米岛上的扫描隧道显微镜针尖所产生的。这些局部电子态能够在特定偏置电压下增强或抑制针尖诱导的表面等离子体激元模式的激发，进而影响诱导光子发射速率。一个定量分析与特征电子态相关的非弹性和弹性隧穿过程的理论模型与实验结果吻合良好。我们还表明，针尖诱导的光子发射测量可用于探测隧穿间隙中的电子态。
