[Study on the CNT sensor for strain measurement and its control method of Raman polarization]

The present paper studied the methodology of carbon nanotube (CNT) sensor applicable for the strain measurement in microscale. Based on the varieties of polarization configurations of the Raman spectrometers, a series of analytic expressions of CNT sensor were derived by applying the Raman properties of the CNT, such as the strain sensitivity and the polarization selectivity. From the viewpoint of metrology, the sensoring relationships corresponding to different polarization configurations were compared and contrasted with one another, which educed that the "bipolar homology" type is most suitable for the strain measurement where both the incident and scattered lights are continuously controllable and always remain parallel to each other. A new easy-realized control method for this configuration is introduced. The experiments proved that the method presented in this paper can effectively measure the in-plane strain components in microscale by polarized micro-Raman spectroscopy.