Design of a Dual-Channel Josephson Array Test System

In response to the growing demand for chip testing, a dual-channel Josephson array test system was designed, incorporating key components such as low-temperature test probes and microwave transmission structures. The test system enables simultaneous measurement of two programmable Josephson devices and provides superimposed voltage output of the two chips. The system's functionalities were validated by measuring a dual-channel programmable Josephson device. The optimal operating frequency of the device is 17 GHz, with an operating power of 11 dBm without a power amplifier. For the dual-channel small voltage programmable Josephson device, the minimum array consists of 1 junction with an output voltage of 35.15 μV, and the maximum array contains 512 junctions with an output voltage of 17998.42 μV. The broadening range of quantum voltage steps is 2 μV. This is due to 34420A (1 V range) noise and testing system noise, which meets the requirements of quantum voltage testing.The dual-channel quantum voltage output is 70.30 μV for a single junction and 35996.84 μV for 512 junctions, the broadening range of quantum voltage steps after superposition is also within 2 μV. This demonstrates that the dual-channel Josephson array test system can not only measure two independent programmable chips but also achieve quantum voltage superimposed output without increasing process difficulty.