Scientists at the Institute of High Energy Physics (IHEP) have developed the country's first 2856 MHz ultrahigh-vacuum (UHV) high-power microwave 4-port differential phase-shift circulator after more than five years of rigorous effort.

The circulator, which fills a key gap in domestic technology, represents an innovative advance as well as a product of great practical importance.

Researchers used specialized welding techniques to join ferrite and oxygen-free copper, overcoming a difficult problem in UHV circulator R&D.

During its successful high-power acceptance test on Nov. 19, the circulator achieved peak RF power of 12 MW with a pulse length of 2 μs and repetition rate of 10 pps under vacuum of 4.8×10^-9 Torr.

Prof. Zhao Fengli of IHEP gave a report on the acceptance test and circulator R&D process at a subsequent expert review meeting. The six scientists in attendance, representing IHEP, the Institute of Electronics, Peking University and other institutions, discussed the circulator test results and welding process. They also visited the test site and checked acceptance indicators.