由于过大的热噪声会导致超流体陀螺无法正常工作,且陀螺的分辨率与热噪声密切相关,因此开展超流体陀螺的热噪声研究有重要意义。利用超流体相位差热波动的标准偏差,建立了超流体陀螺热噪声的数学模型。基于该模型,分析了热噪声对约瑟夫森振荡效应和陀螺分辨率的影响;研究了抑制热噪声的方法。仿真试验表明,增加微孔数量到数千个,并且通过设置工作温度为2.169 K、微孔孔径为70 nm,可以把超流体陀螺的热噪声抑制为10^-9rad/(s·Hz^1/2)的数量级,这时超流体陀螺具有可分辨极小角速度的能力。
Thermal noise is closely related with steady state and resolution of superfluid gyroscope.In this paper,the thermal noise model of superfluid gyroscope was established by using the standard deviation of superfluid's phase difference across the weak link.Based on this model,the impacts of thermal noise on Josephson oscillation effect and gyroscope's resolution were analysed,and the ways to suppress the thermal noise were studied.Simulation results show that,by increasing the number of aperture to thousands and setting the temperature and aperture's diameter to 2.169 K and 70 nm respectively,the thermal noise can be suppressed to the order of 10^-9 rad/(s·Hz^1/2),then the gyroscope has the ability to detect very small angular velocity.