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arXiv · 0801.1626

Linear and Nonlinear Optical constants of BiFeO_3

Amit Kumar·R. Rai·Nikolas Podraza·Sava Denev·Mariola Ramirez·Ying-Hao Chu·Jon Ihlefeld·Tassilo Heeg·Jurgen Schubert·Darrell Schlom·Joseph Orenstein·R. Ramesh·Robert Collins·Janice Musfeldt·Venkatraman Gopalan
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Abstract

Using spectroscopic ellipsometry, the refractive index and absorption versus wavelength of the ferroelectric antiferromagnet Bismuth Ferrite, BiFeO_3 is reported. The material has a direct band-gap at 442 nm wavelength (2.81 eV). Using optical second harmonic generation, the nonlinear optical coefficients were determined to be d_15/d_22 = 0.20 +/- 0.01, d_31/d_22 = 0.35 +/- 0.02, d_33/d_22 = -11.4 +/- 0.20 and |d_22| = 298.4 +/- 6.1 pm/V at a fundamental wavelength of 800 nm.

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Amit Kumar, R. Rai, Nikolas Podraza, Sava Denev, Mariola Ramirez, Ying-Hao Chu, Jon Ihlefeld, Tassilo Heeg, Jurgen Schubert, Darrell Schlom, Joseph Orenstein, R. Ramesh, Robert Collins, Janice Musfeldt, Venkatraman Gopalan. 2008-01-10. Linear and Nonlinear Optical constants of BiFeO_3. https://doi.org/10.1063/1.2901168

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