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Our studies primarily focus on the investigation of atoms and molecules at their intrinsic length scales. To this end, most of our microscopes are operated under ultrahigh-vacuum (UHV) and cryogenic temperature (10K and below) conditions. This allows examining single molecules under clean and stable conditions.

Furthermore, all of our microscopes are equipped with the required toolset for in-situ preparation of atomically flat and clean samples.

Combined Scanning Tunneling/Atomic Force Microscopes

These two equivalent setups are based on a qPlus sensor design, which allows us to perform scanning tunneling microscopy (STM) and atomic force microscopy (AFM) measurements simultaneously. Functionalizing the tip with additional atoms or molecules enables the AFM study of intramolecular phenomena with sub-ångstrom precision. These microscopes are also capable of employing the newly developed AC-STM technique, which allows the investigation of molecular orbitals on insulating surfaces.

Lightwave Scanning Tunneling Microscope

One of the most recent developments in a collaboration with the group of Prof. Rupert Huber at the University of Regensburg culminated in the establishment of lightwave scanning tunneling microscopy (LW-STM). Here, phase-stable laser pulses in the terahertz regime are coupled into the tunneling junction, which act as a transient bias voltage. This permits the manipulation of single electrons on a femtosecond time scale and can be used to track the motion of individual molecules with sub-molecular precision.

2K/9T Scanning Tunneling Microscope

The cryostat of this microscope is equipped with a so-called 1K-pot allowing for a sample temperature of slightly below 2 K, while a solenoid magnet can provide magnetic fields of up to 9 T. This combination of temperature and field allows for inelastic spin-flip excitations to be detected in scanning tunneling spectroscopy, such that this microscope is dedicated to spin-related studies.

mK/10T Scanning Tunneling Microscope

Furthermore, we are setting up a scanning tunneling microscope dedicated to reach lowest temperature in a dilution cryostat, while facilitating sample preparation under ultra-high-vacuum conditions. In scanning tunneling spectroscopy, the temperature determines the energy resolution. Hence, the goal of setting up this apparatus is reaching highest resolution and being able to study very-low energy excitations. We aim at reaching temperatures of 50 mK.

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Latest News

In a recent publication in Science, we report on a novel pump-probe atomic force microscopy, with which we measured the triplet lifetime of individuals molecules.