Local Optical Spectroscopies for Subnanometer Spatial Resolution Chemical Imaging

Weiss, Paul

关键词: nanoscience;    scanning tunneling microscopy;    photoreaction;    solar;   

DOI  :  10.2172/1115418
RP-ID  :  DOE-PSU-15877-F
PID  :  OSTI ID: 1115418

学科分类：纳米科学和纳米技术

美国|英语

来源: SciTech Connect

【 摘 要 】

The evanescently coupled photon scanning tunneling microscopes (STMs) have special requirements in terms of stability and optical access. We have made substantial improvements to the stability, resolution, and noise floor of our custom-built visible-photon STM, and will translate these advances to our infrared instrument. Double vibration isolation of the STM base with a damping system achieved increased rigidity, giving high tunneling junction stability for long-duration and high-power illumination. Light frequency modulation with an optical chopper and phase-sensitive detection now enhance the signal-to-noise ratio of the tunneling junction during irradiation.