Ultrafast vortex arrays generated from a mode-locked oscillator with dispersion management

Area of Science:

• Optics and Photonics
• Laser Physics
• Quantum Optics

Background:

• Optical vortex pulses, characterized by phase singularities, are crucial for advanced optical applications.
• Generating controlled optical vortex arrays requires sophisticated techniques for precise phase and spatial manipulation.

Purpose of the Study:

• To demonstrate a Sagnac common-path interferometric method for generating optical vortex arrays.
• To explore the creation of optical vortex pulses with controllable phase singularities using Hermite-Gaussian (HG) modes.

Main Methods:

• Utilized a SESAM mode-locked laser to generate Hermite-Gaussian (HG) modes in the positive dispersion regime.
• Employed a Sagnac common-path interferometric vortex generator to control phase difference and shearing displacement between HG modes.
• Superposed HG modes to generate optical vortex pulses with varying numbers of phase singularities.

Main Results:

• Successfully generated optical vortex pulses with controllable phase singularities.
• Produced a specific HG10 mode with a 2 ps pulse width and 0.75 nJ maximum energy.
• Demonstrated the generation of one-dimensional and triangular vortex arrays using HG_m0 and HG_0n modes.

Conclusions:

• The Sagnac interferometric approach provides an effective method for generating optical vortex arrays.
• The generated vortex arrays have potential applications in microparticle manipulation and optical communication.
• This technique offers a pathway for the massive manipulation of microparticles and advancements in optical communication systems.