  An experimental investigation of the critical current noise in underdamped
niobium based Josephson junctions by a technique based on the switching current
measurements is reported. By sweeping the junction with a current ramp we
measure the critical current switching using the standard time of flight
technique and analyze the data to extract the current noise. The experimental
results show a linear behavior of the current white noise from both the
junction area and the temperature. These measurement provide very useful
information about the intrinsic noise of Josephson devices involving SQUIDs and
qubits.
