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arXiv · 1309.7485

Physical, optical and nonlinear properties of InS single crystal

Pallavi Kushwaha·Anuradha Patra·E. Anjali·Harshad Surdi·C. Gurada·S. Ramakrishnan·S. S. Prabhu·Venu Gopal Achanta·A. Thamizhavel
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Abstract

Indium Sulphide (InS) single crystals are successfully grown by In flux. Single crystal X-ray diffraction shows orthorhombic structure of Pnnm space group. Ellipsometry measurements performed on the (010) oriented crystal exhibit low anisotropy in the 300-1000 nm wavelength range and consequently negligible THz emission is observed. Optical band gap of $2.09 eV$ is deduced from linear optical measurements. Nonlinear optical properties are studied by single beam Z-scan measurements at 800 nm, where two-photon absorption is present. Nonlinear refractive index and absorption coefficient are estimated to be $η_2$ = $2.3 10^{-11} cm^2/W$ and $β$= $62.4 cm/ GW$, respectively for excitation intensity of $0.32 GW/cm^2$. The origin of nonlinearity in InS crystal is accounted to be due to the third-order anharmonic motion of the bound electrons.

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Pallavi Kushwaha, Anuradha Patra, E. Anjali, Harshad Surdi, C. Gurada, S. Ramakrishnan, S. S. Prabhu, Venu Gopal Achanta, A. Thamizhavel. 2013-09-28. Physical, optical and nonlinear properties of InS single crystal. https://doi.org/10.1016/j.optmat.2013.10.046

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