Four-dimensional light shaping: manipulating ultrafast spatiotemporal foci in space and time

• 来源期刊: 光：科学与应用（英文版）
• 关键词: laser material processing light shaping spatiotemporal focusing ultrafast lasers
• 年，卷（期）: 2018,（1）
• 页码范围: 49-55
• 页数: 7页
• 语种: 英文
• DOI: 10.1038/lsa.2017.117

摘要

The spectral dispersion of ultrashort pulses allows the simultaneous focusing of light in both space and time,which creates socalled spatiotemporal foci.Such space-time coupling may be combined with the existing holographic techniques to give a further dimension of control when generating focal light fields.In the present study,it is shown that a phase-only hologram placed in the pupil plane of an objective and illuminated by a spatially chirped ultrashort pulse can be used to generate threedimensional arrays of spatio-temporally focused spots.By exploiting the pulse front tilt generated at focus when applying simultaneous spatial and temporal focusing (SSTF),it is possible to overlap neighboring foci in time to create a smooth intensity distribution.The resulting light field displays a high level of axial confinement,with experimental demonstrations given through two-photon microscopy and the non-linear laser fabrication of glass.