中国物理B ›› 2018, Vol. 27 ›› Issue (7): 77301-077301.doi: 10.1088/1674-1056/27/7/077301
• SPECIAL TOPIC—Recent advances in thermoelectric materials and devices • 上一篇 下一篇
Chaoyu Guo(郭钞宇), Xiangzhi Meng(孟祥志), Qin Wang(王钦), Ying Jiang(江颖)
Chaoyu Guo(郭钞宇)1, Xiangzhi Meng(孟祥志)1, Qin Wang(王钦)1, Ying Jiang(江颖)1,2,3
摘要:
The plasmon-enhanced light emission of rutile TiO2(110) surface has been investigated by a low-temperature scanning tunneling microscope (STM). We found that the photon emission arises from the inelastic electron tunneling between the STM tip and the conduction band or defect states of TiO2(110). In contrast to the Au(111) surface, the maximum photon energy as a function of the bias voltage clearly deviates from the linear scaling behavior, suggesting the non-negligible effect of the STM tip on the band structure of TiO2. By performing differential conductance (dI/dV) measurements, it was revealed that such a deviation is not related to the tip-induced band bending, but is attributed to the image charge effect of the metal tip, which significantly shifts the band edges of the TiO2(110) towards the Femi level (EF) during the tunneling process. This work not only sheds new lights onto the understanding of plasmon-enhanced light emission of semiconductor surfaces, but also opens up a new avenue for engineering the plasmon-mediated interfacial charge transfer in molecular and semiconducting materials.
中图分类号: (Electron states at surfaces and interfaces)