Sensitive measurement of optical nonlinearity in amorphous chalcogenide materials in nanosecond regime

详细信息	查看全文 | 推荐本文 |

• 作者：Sunita Rani ; ^{sgarhwal48@gmail.com} ; Devendra Mohan¹ ; Nawal Kishore¹ ; Purnima¹
• 关键词：Chalcogenide material ; Optical limiting ; Nonlinear refractive index ; Two photon absorption ; Limiting threshold
• 刊名：Spectrochimica Acta Part A ; Molecular and Biomolecular Spectroscopy
• 出版年：2012
• 期刊代码：99_13861425
• 类别：ch
• 出版时间：July, 2012
• 卷：93
• 期：Complete
• 页码：135-139
• 文件大小：631 K

摘要

The present work focuses on the nonlinear optical behavior of chalcogenide As₂S₃ film as well as on bulk material. The thin film of As₂S₃ grown by thermal evaporation and bulk glass developed by melt-quenched technique has been characterized using nanosecond pulses of Nd:YAG (532 nm) and Nd:YVO₄ (1064 nm) laser. Using Z-scan technique, the laser induced nonlinear optical parameters viz. nonlinear refractive index (n₂), nonlinear absorption coefficient (尾) and third order nonlinear susceptibility (蠂³) have been estimated. At 1064 nm excitation, the materials exhibit stronger nonlinearity as compared to that of 532 nm laser. In case of As₂S₃ thin film, observed nonlinearity attributes to two-photon absorption. The optical limiting response of chalcogenide film as well as bulk sample has also been reported. The study predicts that the As₂S₃ thin film is a better optical limiting material than bulk glass due to relatively higher nonlinearity and lower limiting threshold.