Probing large area surface plasmon interference in thin metal films using photon scanning tunneling microscopy

Area of Science:

• Optics and Photonics
• Surface Science
• Condensed Matter Physics

Background:

• Surface plasmons offer insights into thin metal film properties.
• Understanding surface plasmon interference is crucial for surface characterization.

Purpose of the Study:

• To investigate the interference of optically excited surface plasmons.
• To analyze surface plasmon interference patterns in the visible spectrum using the Kretschmann configuration.

Main Methods:

• Excitation of surface plasmons in thin metal films.
• Utilizing the Kretschmann configuration for optical coupling.
• Imaging interference regions with a photon scanning tunneling microscope (PSTM).
• Modeling the probe-metal system using confocal hyperboloids in spheroidal coordinates.

Main Results:

• Generation of large-area surface plasmon interference regions at various wavelengths.
• Successful imaging of these interference patterns with PSTM.
• Discussion of non-retarded dispersion relations for surface plasmons.

Conclusions:

• Surface plasmon interference is a viable technique for probing thin metal film surfaces.
• The Kretschmann configuration and PSTM are effective tools for this investigation.
• Theoretical modeling provides a framework for understanding surface plasmon behavior in specific geometries.