Transmission line probes for scanning photon-tunneling microscopy

Area of Science:

• Optics
• Microscopy
• Waveguide Technology

Background:

• Metalized light probes for scanning photon-tunneling microscopy function as tapered waveguides beyond their cutoff frequency.
• Tapered coaxial transmission lines have been investigated as an alternative to these probes.

Purpose of the Study:

• To investigate methods for reducing insertion losses in tapered coaxial transmission lines used in scanning photon-tunneling microscopy.
• To explore alternative waveguide structures for improved performance.

Main Methods:

• Analyzing the insertion losses of tapered coaxial transmission lines.
• Implementing asymmetric phase-apodization of the illuminating lens.
• Comparing the performance of coaxial lines with strip lines.

Main Results:

• Insertion losses in tapered coaxial lines can be significantly reduced through asymmetric phase-apodization of the illuminating lens.
• The use of a strip line presents a viable alternative to coaxial lines for this application.
• These modifications offer improved efficiency for light probes in scanning photon-tunneling microscopy.

Conclusions:

• Asymmetric phase-apodization is an effective technique to minimize signal loss in tapered coaxial transmission lines.
• Strip lines offer a promising alternative for constructing efficient light probes in scanning photon-tunneling microscopy.
• The findings contribute to the development of more sensitive and effective microscopy techniques.