Physikalisch-Technische Bundesanstalt

Tasks

Our activities are focused on the investigation of the normal and superconducting metallic circuits including tunnel junctions and exhibiting behaviour resulted from the quantum nature of the two conjugate variables, i.e. the electric charge Q and the magnetic flux . The control of individual quanta of charge (e and 2e) and flux ( = h/2e) makes it possible to design electronic devices which open the ways to the realization of fundamental quantum standards for electrical quantities and systems for processing digital information. The operation of charge-based devices utilizes either the principle of tunnelling of single electrons in normal-state circuits, i.e. SET, or the principle of Josephson tunnelling of single Cooper pairs (each carrying a charge 2e) in superconducting circuits. The operation of the single flux quantum circuits, the so-called RSFQ circuits (where R stands for "rapid" emphasizing potentially high speed of their operation), is based on dynamics of overdamped Josephson junctions.

Main tasks of the group are:

• Designing and manufacturing of single-electron circuits, the so-called R-pumps and readout electrometers, applied for implementation of quantum standard of capacitances based on accurate counting of single electrons
  
  
• Development and investigation of superconducting single Cooper pair circuits of 1D-array configuration with the goal of realization of fast clocked tunnelling of individual pairs
  
  
• Development of special single flux quantum circuits integrated with Josephson quantum bit circuits and single Cooper pair circuits with the goal of their efficient control and readout

Contact

Head of Working Group		Dr. Alexander Zorin Phone: ++ 49 - 531-592-2400 E-Mail: Alexander Zorin
Address		Physikalisch-Technische Bundesanstalt AG 2.42 Bundesallee 100 38116 Braunschweig GERMANY