Micro-Raman spectroscopic visualization of lattice vibrations and strain in He- implanted single-crystal LiNbO3

Scanning micro-Raman spectroscopy has been utilized to image and investigate strain in He-implanted congruent LiNbO3 samples. By using abruptly patterned implanted samples, we show that the spatial twodimensional mapping of the Raman spectral peaks can be used to image the strain distribution and determine its absolute magnitude. We demonstrate that both shortand long-range length-scale in-plane and out-of-plane strain and stress states can be determined using the secular equations of phonondeformation-potential theory. We also show that two-dimensional Raman imaging can be used to visualize the relaxation of strain in the crystal during low-temperature annealing. ©2014 Optical Society of America OCIS codes: (130.3730) Lithium niobate; (160.4670) Optical materials; (300.6450) Spectroscopy, Raman; (310.3840) Materials and process characterization. References and links 1. M. E. Lines and A. M. 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