研制了一种高均匀性、小型化的法拉第磁光隔离器,用于780 nm波长的光路中,并对设计方案进行了数值模拟和验证。采用了新颖的三段式“π”形磁体的组合设计方案,提高了剩磁利用率.隔离器整体体积为52 cm^3,其中磁体体积为18 cm^3,是相当小的。它的通光孔径为5 mm,隔离比为34.6 dB,透过率为90.9%。与之类似的“Ⅱ”型磁体体积更小,磁场均匀性稍差,也是可行的设计方案。成品隔离器比商用隔离器磁场均匀度更高,体积更小,隔离比更高,可以有效满足研发中的冷原子平台的小型化、高精度需求。
An improved design of Faraday optical isolator at 780nm was developed.Numerical simulation was used to confirm the design. It has advantage of more uniform magnetic field, smaller size and better isolation. This design of magnet called style " π " divides a whole hollow cylinder into 3 parts including several fan-shaped magnets. It can increase the use ratio of the remanence of magnet. The design of one-stage isolator has a volume of 52 cm3 with a volume of magnet of 18 cm3, which is small. The optical clear aperture is 5 mm with a 34.6 dB isolation and 90.9% transmission rate. Style " II " may also be optional for having a smaller volume but less uniformed magnets. The isolator developed according to style " 7r " has better performance than common used optical isolators in terms of atomic, molecular and optics (AMO) physics at the special wavelength of 780 nm in order to meet the demands of the ultracold atom system.