Broadband nulling of a vortex phase mask.

Area of Science:

• Optics and Photonics
• Quantum Information Science

Background:

• Helical vortex phase masks are crucial optical elements for shaping light.
• Understanding light-matter interactions with vortex beams is key for advanced applications.

Purpose of the Study:

• To investigate the spectral properties of light pulses transmitted through helical vortex phase masks.
• To analyze the energy transfer into undesired modes as a function of optical parameters.

Main Methods:

• Theoretical analysis of a light pulse interacting with a helical vortex phase mask.
• Mathematical modeling of the transmitted pulse's spectral components.

Main Results:

• The helical vortex phase mask performs a temporal Hilbert transform on the transmitted pulse.
• Energy coupling into the plane wave mode scales quadratically with optical bandwidth.
• This energy transfer is largely independent of the vortex's topological charge.

Conclusions:

• The bandwidth of the light pulse is a critical factor for energy leakage into plane wave modes.
• Topological charge does not significantly influence this energy loss mechanism.
• Findings are relevant for designing high-fidelity vortex beam applications.