Ultrafast multi-target control of tightly focused light fields

• 作者: Yanxiang Zhang Xiaofei Liu Han Lin Dan Wang Ensi Cao Shaoding Liu Zhongquan Nie Baohua Jia
• 来源期刊: 光电进展（英文版）
• 年，卷（期）: 2022,（3）
• 所属期刊栏目: Original Article
• 页码范围: 76-87
• 页数: 12页
• 语种: 英文
• DOI: 10.29026/oea.2022.210026

摘要

The control of ultrafast optical field is of great interest in developing ultrafast optics as well as the investigation on vari-ous light-matter interactions with ultrashort pulses. However, conventional spatial encoding approaches have only lim-ited steerable targets usually neglecting the temporal effect, thus hindering their broad applications. Here we present a new concept for realizing ultrafast modulation of multi-target focal fields based on the facile combination of time-depend-ent vectorial diffraction theory with fast Fourier transform. This is achieved by focusing femtosecond pulsed light carrying vectorial-vortex by a single objective lens under tight focusing condition. It is uncovered that the ultrafast temporal de-gree of freedom within a configurable temporal duration (～400 fs) plays a pivotal role in determining the rich and exotic features of the focused optical field at one time, namely, bright-dark alternation, periodic rotation, and longitudinal/trans-verse polarization conversion. The underlying control mechanisms have been unveiled. Besides being of academic in-terest in diverse ultrafast spectral regimes, these peculiar behaviors of the space-time evolutionary beams may underpin prolific ultrafast-related applications such as multifunctional integrated optical chip, high-efficiency laser trapping, micro-structure rotation, super-resolution optical microscopy, precise optical measurement, and liveness tracking.