Third-order nonlinear optical effects were proposed for simultaneous speed modulation of optical and mechanical waves in bismuth telluride nanostructures assisted by an optical two-wave mixing. The optical nonlinearities were investigated under excitation with nanosecond laser pulses at a wavelength of 532 nm. The Bi₂Te₃ nanostructures were prepared by a simple chemical process. Standard characterization by electrochemical impedance spectroscopy, ellipsometry, UV–Vis absorption and Fourier transform infrared spectrometry was undertaken. The phase purity and vibrational mode of the Bi₂Te₃ were determined by X-ray diffraction studies and Raman spectroscopy, respectively. The nanocrystal structure and morphology of the Bi₂Te₃ sample were identified by High-Resolution Transmission Electron Microscopy. The structural characterization and chemical composition of the nanostructures were carried out by Scanning Electron Microscopy combined with Energy Dispersive X-ray spectroscopy. The nanostructured nature of this topological insulator seems to be responsible of its unique polarization-selectable nonlinear optical response. Potential applications for developing structured light systems can be contemplated.

提出了三阶非线性光学效应，以通过光学两波混合辅助同时调制碲化铋纳米结构中的光波和机械波。在波长为532 nm的纳秒激光脉冲激发下研究了光学非线性。通过简单的化学方法制备了Bi ₂ Te ₃纳米结构。通过电化学阻抗光谱法，椭圆偏振法，UV-Vis吸收法和傅立叶变换红外光谱法进行了标准表征。通过X射线衍射研究和拉曼光谱法分别测定了Bi ₂ Te ₃的相纯度和振动模式。Bi ₂的纳米晶体结构和形态通过高分辨率透射电子显微镜鉴定了Te ₃样品。纳米结构的结构表征和化学组成通过扫描电子显微镜结合能量色散X射线光谱法进行。这种拓扑绝缘体的纳米结构性质似乎是其独特的偏振可选非线性光学响应的​​原因。可以考虑开发结构化照明系统的潜在应用。