Visible optical vortices measured with bulk lateral shearing interferometry.

Area of Science:

• Quantum Optics and Photonics
• Ultrafast Laser Science
• Nonlinear Optics

Background:

• Ultrafast pulse optical vortices are crucial spatiotemporal structures with broad applications.
• Current generation methods are often wavelength-restricted, limiting their utility.
• Existing characterization techniques share similar spectral limitations.

Purpose of the Study:

• To generate ultrashort optical vortices in the visible spectrum.
• To demonstrate a versatile spatiotemporal characterization method for these visible pulses.
• To validate the use of bulk lateral shearing interferometry across different spectral regions.

Main Methods:

• Generation of near-infrared ultrafast optical vortices using Ti:sapphire laser pulses, structured waveplates, and beam manipulation.
• Visible vortex production via second-harmonic generation (up-conversion).
• Spatiotemporal characterization using bulk lateral shearing interferometry and temporal characterization via the amplitude swing technique.

Main Results:

• Successful generation of visible ultrafast optical vortices.
• Experimental validation of the visible vortex generation.
• Demonstration that bulk lateral shearing interferometry can characterize pulsed beams across widely different spectral regions using the same setup.

Conclusions:

• Visible ultrafast optical vortices can be generated through nonlinear up-conversion.
• Bulk lateral shearing interferometry is a robust and versatile technique for characterizing ultrafast pulsed beams in both near-infrared and visible spectral regions.
• This finding broadens the applicability of optical vortices and their characterization for future scientific and technological advancements.