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arXiv · 1407.4271

BiFeO3 nanocrystals for bio-imaging based on nonlinear optical harmonic generation

Sebastian Schwung·Andrii Rogov·Gareth Clarke·Cécile Joulaud·Thibaud Magouroux·Davide Staedler·Solène Passemard·Thomas Jüstel·Laurent Badie·Christine Galez·Jean Pierre Wolf·Yuri Volkov·Adriele Prina-Mello·Sandrine Gerber-Lemaire·Daniel Rytz·Yannick Mugnier·Luigi Bonacina·Ronan Le Dantec
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Abstract

Second Harmonic Generation (SHG) from BiFeO3 nanocrystals is investigated for the first time to determine their potential as biomarkers for multiphoton imaging. Nanocrystals are produced by an auto-combustion method with TRIS as a fuel. Stable colloidal suspensions with mean particle diameters in the range 100-120 nm are then obtained after wet-milling and sonication steps. SHG properties are determined using two complementary experimental techniques, Hyper Rayleigh Scattering and nonlinear polarization microscopy. BiFeO3 shows a very high second harmonic efficiency with an averaged coefficient of 79+-12 pm/V. From the nonlinear polarization response of individual nanocrystals, relative values of the independent dij coefficients are also determined and compared with recent theoretical and experimental studies. Additionally, the particles show a moderate magnetic response, which is attributed to gamma-Fe2O3 impurities. A combination of high nonlinear optical efficiency and magnetic response within the same particle is of great interest for future bio-imaging and diagnostic applications.

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Sebastian Schwung, Andrii Rogov, Gareth Clarke, Cécile Joulaud, Thibaud Magouroux, Davide Staedler, Solène Passemard, Thomas Jüstel, Laurent Badie, Christine Galez, Jean Pierre Wolf, Yuri Volkov, Adriele Prina-Mello, Sandrine Gerber-Lemaire, Daniel Rytz, Yannick Mugnier, Luigi Bonacina, Ronan Le Dantec. 2014-07-16. BiFeO3 nanocrystals for bio-imaging based on nonlinear optical harmonic generation. https://arxiv.org/abs/1407.4271

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