Ultimate SPM Performance below 5K

New concept for advanced optical experiments

Optical spectroscopy techniques like near-infrared, Tip Enhanced Raman Spectroscopy (TERS) or low-temperature fluorescence provide detailed information about the chemical and enviromental structure on organic systems. Here, we introduce our new concept for advanced optical experiments at helium temperature in ultra-high vacuum environment.

To guarantee best optical conditions, the optical integration is optimised on the following key factors:

  • Highest detection efficiency is provided by the numerical aperture (NA) of NA = 0.39 which results in a theoretical focus diameter of 835nm at 532nm excitation wavelength.
  • The angle of incidence in this setup is optimised to 30°.
  • Three piezo-motors allow the adjustment of the lens in the full temperature range from 4.5K to 300K.
  • The x/y piezo motor is moving within the sample coordinate system, while the z-piezo motor is oriented along the optical axis of the lens. This ensures convenient operation of the optical setup.

In combination with the proven performance of the LT STM, this modification allows a broad range of new and exciting experiments.

2018 TERS for LT STM
PDF  1.56 MB