Single-microwave quantum amplifier based on ultra-narrow band filtering and back-crossing effect

The invention provides a single-microwave quantum amplifier based on ultra-narrow-band filtering and a back-crossing effect. The single-microwave quantum amplifier comprises a single microwave quantumsource, a broadband microwave noise source, a microwave low-noise linear amplifier, a microwave isolator and a first ultra-narrow-band microwave filter, the single microwave quantum output by the single microwave quantum source and the thermal noise output by the broadband microwave noise source are mixed and input into the microwave low-noise linear amplifier; the microwave low-noise linear amplifier amplifies the input mixed signal; after passing through a microwave isolator, the amplified signal is input into a first ultra-narrow band microwave filter, so that amplification of single microwave quantum is realized; and the bandwidth of the first ultra-narrow band microwave filter is in kHz magnitude. Components used in the method are mature in technology and stable in performance, all the components can work at