...
首页> 外文期刊>Optical Engineering >Third harmonic microscopy of intrinsic and induced material anisotropy in dielectric thin films
【24h】

Third harmonic microscopy of intrinsic and induced material anisotropy in dielectric thin films

机译:Third harmonic microscopy of intrinsic and induced material anisotropy in dielectric thin films

获取原文
获取原文并翻译 | 示例
           

摘要

Third harmonic (TH) microscopy with circularly polarized illumination directly reveals material anisotropy owing to suppression of background optical signals from isotropic media. Because optical thin films and their substrates are expected to be highly isotropic, TH microscopy presents a path to study induced and intrinsic anisotropy in films, providing both insight into laser-induced material modification that precedes damage and feedback about the deposition process. Because nanoscale defects and material strain influence the damage behavior of films, we examined TH sensitivity to similar sources of contrast. We demonstrate imaging of individual 10 nm colloidal gold nano-particles and 100 mN nanoindentations in fused silica both with signal-to-noise ratio (SNR) ≥ 100:1. We present TH images (SNR ≥ 210:1) of sites exposed to femtosecond laser pulses below damage in 100 nm HfO_2 films that are barely visible (SNR ≤ 2.3:1) with Nomarski and polarization imaging, traditional microscopic techniques known to display contrast for material anisotropy. At our detection limit (320 mW, 50 fs, 790 nm, ≈10~6 photomultiplier tube gain), we examined root mean square in the TH image of nascent films that correlated to the film's macrostrain. TH microscopy presents a relatively simple all-optical method to monitor nanoscale anisotropy in thin films during exposure to high-intensity radiation and during deposition.

著录项

获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号