Effective method for photonic jet shaping in reflection mode

Area of Science:

• Optics and Photonics
• Materials Science
• Nanotechnology

Background:

• Photonic jets (PJ) are highly directional light beams generated by subwavelength dielectric scatterers.
• Controlling and shaping PJs is crucial for applications in optical trapping, sensing, and microscopy.
• Existing methods for PJ shaping have limitations in the range of control and effectiveness.

Purpose of the Study:

• To investigate an effective method for shaping photonic jets (PJ) using dielectric cuboid scatterers on a hollow reflection screen.
• To analyze the influence of geometric parameters of the cuboid and hollow screen on PJ characteristics.
• To compare the efficacy of this new shaping method with previous techniques.

Main Methods:

• Utilized dielectric cuboid scatterers positioned on a hollow reflection screen.
• Systematically varied geometric parameters: cuboid side length, depth, and hollow position.
• Analyzed photonic jet characteristics including intensity, focal length (FL), and lateral size.
• Employed ray optics and electromagnetic field theory for theoretical explanation.

Main Results:

• All geometric parameters (side length, depth, position) effectively shaped the PJ's intensity, FL, and lateral size.
• The proposed method demonstrated a superior shaping capability with three times larger varying ranges compared to prior methods.
• Hollow position was found to primarily influence the PJ's propagation trajectory, inducing curvature due to asymmetry.

Conclusions:

• The presented method offers a highly effective and superior approach to shaping photonic jets.
• Geometric manipulation of cuboid and hollow screen parameters provides significant control over PJ properties.
• Understanding the role of hollow-induced phase singularity and positional asymmetry is key to controlling PJ trajectory.