  Using a point (superconductor-constriction-superconductor, ScS) contact in a
single-Josephson-junction superconducting quantum interference device (RF
SQUID) provides stochastic resonance conditions at any arbitrary small value of
loop inductance and contact critical current, unlike SQUIDs with more
traditional tunnel (superconductor-insulator-superconductor, SIS) junctions.
This is due to the unusual potential energy of the ScS RF SQUID which always
has a barrier between two wells thus making the device bistable. This paper
presents the results of a numerical simulation of the stochastic dynamics of
the magnetic flux in an ScS RF SQUID loop affected by band-limited white
Gaussian noise and low-frequency sine signals of small and moderate amplitudes.
The difference in stochastic amplification of RF SQUID loops incorporating ScS
and SIS junctions is discussed.
