Editing Electron mobility (section)

===Optical mobility===
Electron mobility may be determined from non-contact laser [[photo-reflectance technique]] measurements. A series of photo-reflectance measurements are made as the sample is stepped through focus.  The electron diffusion length and recombination time are determined by a regressive fit to the data. Then the Einstein relation is used to calculate the mobility.<ref>W. Chism, "Precise Optical Measurement of Carrier Mobilities Using Z-scanning Laser Photoreflectance," [https://arxiv.org/abs/1711.01138 arXiv:1711.01138] [physics:ins-det], Oct. 2017.</ref><ref>W. Chism, "Z-scanning Laser Photoreflectance as a Tool for Characterization of Electronic Transport Properties," [https://arxiv.org/abs/1808.01897 arXiv:1808.01897] [cond-mat:mes-hall], Aug. 2018.</ref>