Scanning voltage microscopy
This article needs to be updated.(April 2021) |
Scanning voltage microscopy (SVM), sometimes also called nanopotentiometry, is a scientific experimental technique based on
Applications
SVM is particularly well suited to analyzing
For example, the potential profile across the quantum well structure of a diode laser can be mapped and analyzed; such a profile could indicate the electron and hole distributions where light is generated and could lead to improved laser designs.
Scanning gate microscopy
In a similar technique, scanning gate microscopy (SGM), the probe is oscillated at some natural frequency some fixed distance above the sample with an applied voltage relative to the sample. The image is constructed from the X,Y position of the probe and the conductance of the sample, with no significant current passing through the probe, which acts as a local gate. The image is interpreted as a map of the sample's sensitivity to gate voltage. A lock-in amplifier aids noise reduction by filtering through only the amplitude oscillations that match the probe's vibration frequency. Applications include imaging defect sites in carbon nanotubes and doping profiles in nanowires.
References
- ^ ISBN 978-0-387-28668-6.
- ISBN 978-0-387-28668-6, retrieved 2021-04-22
- ISSN 1040-8436.