Scanning Microwave Impedance Microscopy (MIM) measurement of photoconductivity with 50 nm resolution is demonstrated using a modulated optical source. The use of a modulated source allows for measurement of photoconductivity in a single scan without a reference region on the sample, as well as removing most topographical artifacts and enhancing signal to noise as compared with unmodulated measurement. A broadband light source with tunable monochrometer is then used to measure energy resolved photoconductivity with the same methodology. Finally, a pulsed optical source is used to measure local photo-carrier lifetimes via MIM, using the same 50 nm resolution tip.
@article{arxiv.1710.10239,
title = {Optically Coupled Methods for Microwave Impedance Microscopy},
author = {Scott R. Johnston and Eric Yue Ma and Zhi-Xun Shen},
journal= {arXiv preprint arXiv:1710.10239},
year = {2018}
}