Effect of Thermal Noise and Trigger Jitter on the Operation of HTS Sampler

We have studied the effect of thermal noise and trigger jitter on the bandwidth of a high-T
_c
superconducting sampler by computer simulation and analytical calculation. Simulation results showed that the minimum I
_c
R
_n
product of the junctions required to obtain 100-GHz bandwidth is raised from 0.63 to 0.75 mV under the influence of the thermal noise at 40K. On the other hand, the maximum trigger jitter for 100-GHz bandwidth is 1.87 ps when only an averaging effect is assumed. Considering both the effects of thermal noise and trigger jitter, we found, for example, that trigger jitter must be reduced down to 1 ps to realize the bandwidth above 100 GHz with an I
_c
R
_n
product of 1 mV at an operating temperature of 40 K