Mechanically Controllable Break Junction
Cryogenic type of mechanically controllable Break Junction
Frequency dependent measurements at different temperatures ranging from room-temperature to 4K provide information about the mechanism of charge transfer in complex molecules. This enables us to understand charge transfer in organic molecules.
Equipment and Measurements
Mechanically Controllable Break Junctions represent an ideal method to investigate electronic and mechanical properties of single molecules. A lithographically defined nano-Au-conctact on a flexible substrate is mechanically controlled by the reversible bending of the substrate via a piezo-crystal. Well defined vertical movements of the piezo bend the substrate and as a result separate the junction.
Due to the precise moving of the piezo crystal and the attenuation factor from vertical movement to horizontal movement, a very small gap between the two gold tips can be controlled on subnanometer size. The molecules are placed between the tips and mechanical and electronic properties of the molecules can be analyzed.
Furthermore, for temperature dependent measurements the break-junction setup is placed in a cryostat, temperature range 4 to 300K. A magnet is available providing magnetic fields up to 0.5T.