Research area: NONLINEAR MICRO- AND NANOELECTRONICS
Under this aspect of the program, it is proposed that new types of cryogenic
electronic components will be designed and fabricated, which are based on
superconducting materials and on combinations of superconductors and
heterostructures of semiconductors and semimetals. Experimental and
theroretical investigations are bring carried out on nonlinear superconductors,
on mesoscopic, superconductor-semiconductor components and devices and on single
electron tunneling effects. These new electronic components share one
feature: they are very fast and sensitive because they involve temporal or
spatial coherence which stem from quantum and/or mesoscopic effects in minute
volumes (micro- or nano-scale electronics).
In long Josephson junctions magnetic flux quanta are modelled as sine-Gordon
solitons (`fluxons') and their dynamic behaviour is calculated both
analytically and numerically and compared with experimental measurements. These
effects are enhanced by the use of arrays of coupled junctions. In
superconducting transistors the much reduced ohmic losses imply improvements of
the device transit frequency.
In practice, the research efforts are focussed on the following types of
electronic components and devices: Single Electron Transistors (SETs),
Superconducting Field Effect Transistors (SUPRAFETs), Rapid Single Flux Quantum
electronics (RSFQ), Superconducting Quantum Interference Devices (SQUIDs) and
Josephson oscillators. The research is carried out in collaboration with NKT
Research Center A/S.