Josephson phase diffusion in the superconducting quantum interference device ratchet

Superconducting quantum interference device instruments and applications

Superconducting quantum interference devices SQUIDs have been a key factor in the development and commercialization of ultrasensitive electric and magnetic measurement systems. In many cases, SQUID instrumentation offers the ability to make measurements where no other methodology is possible. We review the main aspects of designing, fabricating, and operating a number of SQUID measurement syste...

Microstrip Superconducting Quantum Interference Device Amplifiers with Submicron Josephson Junctions: Enhanced Gain at Gigahertz Frequencies

Quantum charge diffusion in underdamped Josephson junctions and superconducting nanowires

The effect of quantum fluctuations on the current-voltage characteristics of Josephson junctions and superconducting nanowires is studied in the underdamped limit. Quantum fluctuations induce transitions between a Coulomb–blockade and a supercurrent branch, and can significantly modify the shape of current-voltage characteristics in the case of a highly resistive environment. Owing to the phase...

Scanning superconducting quantum interference device microscope in a dilution refrigerator

We report on a scanning superconducting quantum interference device microscope operating at temperatures down to 20 mK in a dilution refrigerator. The instrument is designed for studying quantum mechanical coherence effects in mesoscopic systems and investigating magnetic effects on a mesoscopic length scale in novel materials. We have demonstrated the low-temperature operating capabilities of ...

Quantum Interference in Josephson Junctions

The parallelism between diffraction and interference in optics and quantum interference in Josephson junctions is discussed and studied in details. The interdisciplinary character of the present work is highlighted through specific examples. The Fraunhofer-like pattern of the maximum Josephson current in a single Josephson junction and the periodic field dependence of the critical current in tw...