Tunable SNAP microresonators via internal ohmic heating

Area of Science:

• Photonics
• Materials Science
• Nanotechnology

Background:

• Surface Nanoscale Axial Photonics (SNAP) offers unique optical properties.
• Precise control over SNAP structures is crucial for advanced applications.
• Existing tuning methods may lack the required precision or stability.

Purpose of the Study:

• To demonstrate a novel thermally tunable SNAP platform.
• To achieve stable and precise control over SNAP microresonator wavelengths.
• To enable new functionalities like temporary microresonators and differential tuning.

Main Methods:

• Fabrication of SNAP structures on silica capillary surfaces.
• Integration of internal metal wires for resistive heating.
• Application of uniform and non-uniform heating for spectral control.
• Demonstration with coupled bottle microresonators.

Main Results:

• Achieved stable and uniform wavelength shifts via uniform heating.
• Enabled local nanoscale radius variation using non-uniform heating.
• Demonstrated differential tuning of coupled microresonators with <0.2 pm precision.
• Created temporary SNAP microresonators activated by current.

Conclusions:

• The developed thermal tuning approach provides ultra-precise control over SNAP devices.
• This method is beneficial for fabricating tunable parity-time symmetric, optomechanical, and cavity quantum electrodynamics (QED) devices.
• The platform opens new avenues for advanced photonic integrated circuits.