A Performance Testing Method of Josephson Parametric Amplifier

Abstract

The invention belongs to the field of amplifier test, and discloses a performance test method for a Josephson parametric amplifier. The performance test method comprises the following steps: measuringa first gain curve of the Josephson parametric amplifier according to a first reference parameter, and determining a second reference parameter corresponding to a gain interval satisfying a preset gain threshold range on the first gain curve; measuring a second gain curve of the Josephson parametric amplifier according to a second reference parameter; determining a third reference parameter according to a maximum gain bandwidth value on the second gain curve; measuring a third gain curve of the Josephson parametric amplifier according to the third reference parameter; and determining an optimal operating point parameter according to the maximum gain bandwidth value on the third gain curve. According to the performance test method for the Josephson parametric amplifier provided by the invention, each measurement is based on a previous measurement result, thus the blindness and the data acquisition quantity of the test work are reduced, and the performance test work of the Josephson parametric amplifier is effectively improved.

Description

technical field [0001] The invention belongs to the field of amplifier testing, in particular to a performance testing method of a Josephson parametric amplifier. Background technique [0002] In superconducting quantum computing, the superconducting quantum chip is in an extremely low temperature (<30mK) environment, which is greatly affected by noise, and the output signal from the superconducting quantum chip is very weak. Generally, it is necessary to add a multi-stage amplifier after the output end Used to increase signal strength. At present, commercial cryogenic amplifiers generally work in the 4K temperature layer, which will bring great thermal noise, while the Josephson parametric amplifier that works in the same temperature layer as the superconducting quantum chip has a great gain and does not introduce additional noise. characteristics, so the Josephson parametric amplifier is a necessary device for superconducting quantum computing. [0003] The performanc...

AI Technical Summary

Problems solved by technology

[0005] 1. The existing technology repeatedly scans the pump power and bias current in a large range at a fixed pump frequency to observe the gain of each operating point, then replaces the pump frequency and repeats the above steps. The blindness is too high, and this Slightly repetitive blind scanning obtains a large amount of data, increases the workload of data analysis, increases the difficulty of data processing, and greatly reduces the performance test efficiency of Josephson parametric amplifiers

[0006] 2. In the existing technology, the bias current, pump frequency and pump power are repeatedly scanned in a large range, and the scanning time is long and extremely time-consuming

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