High-Speed Nonlinear Interferometric Vibrational Imaging of Biological Tissue With Comparison to Raman Microscopy

• Published in: IEEE journal of quantum electronics 2010-07, Vol.16 (4), p.824-832
• Main Authors: Benalcazar, W A, Chowdary, P D, Zhi Jiang, Marks, D L, Chaney, E J, Gruebele, M, Boppart, S A
• Format: Article
• Language: English
• Subjects: Biological; Biological materials; Biological tissue; Biological tissues; Broadband; Cars; Chirp; coherent anti-Stokes Raman scattering (CARS); High-resolution imaging; Image resolution; Image retrieval; Imaging; interferometry; Microscopy; nonlinear interferometric vibrational imaging (NIVI); Nonlinearity; optical imaging; Phase detection; Pumps; Raman scattering; Resonance; Spectra; spectroscopy
• ISSN: 1077-260X; 0018-9197; 1558-4542
• DOI: 10.1109/JSTQE.2009.2035537

Vibrational contrast imaging of the distribution of complex biological molecules requires the use of techniques that provide broadband spectra with sufficient resolution. Coherent anti-Stokes Raman scattering (CARS) microscopy is currently limited in meeting these requirements due to the presence of a nonresonant background and its inability to target multiple resonances simultaneously. We present nonlinear interferometric vibrational imaging (NIVI), a technique based on CARS that uses femtosecond pump and Stokes pulses to retrieve broadband vibrational spectra over 200 cm -1 (full-width at half maximum). By chirping the pump and performing spectral interferometric detection, the anti-Stokes pulses are resolved in time. This phase-sensitive detection allows suppression of not only the nonresonant background, but also of the real part of the nonlinear susceptibility χ (3) , improving the spectral resolution and features to make them comparable to those acquired with spontaneous Raman microscopy, as shown for a material sample and mammary tissue.