A transition edge sensor signal simulator to evaluate the performance of superconducting quantum interference device amplifier

SQUIDs can be used as amplifiers for superconducting Transition Edge Sensor (TES) photon counting detectors. According to the physical process of photon counting, a TES signal simulator was developed to evaluate the performance of SQUID amplifier for TES detectors. A triangle simulation signal was determined to be a close match to that from a real TES photon counter. The dynamic range for the output voltage versus bias current was first characterized and then the current signals were incrementally coupled to circuit to determine the highest sensitivity of a series-array SQUID amplifier. The sensitivities are obtained by changing the triangle signal amplitude added to the TES signal simulator. The impedance changes can be deduced and further obtain the temperature changes of TES devices. When knowing the photon energy, TES design parameters can be known according to the thermal characteristics. In conclusion, the TES simulator can be well applied to guide the device design for effective readout.