光-原子混合干涉实现加速度测量

Atom-light hybrid interference to achieve acceleration measurement

基于光-原子混合干涉仪构建了一种新型的光-原子相位自锁定的加速度计.虽然在目前所有加速度计中,全光类型的加速度计由于其体积小、精度高,成为了最常用且也是最稳定的加速度计;但由于其测量带宽受到的限制,所以极大地限制了其使用的范围.基于此,设计了一种新型的光-原子加速度计(Atom-Light Accelerometer,ALA).该加速度计的特点:首先,在原子系统中通过受激拉曼散射(Stimulated Raman Scattering,SRS)过程构成光-原子混合干涉仪;其次,由反射镜构成加速度计的弹性质量块,在实验平台上,当质量块受到一个加速度作用时,就会接收到外界带来的位移的变化,从而将相位的变化引入到干涉仪中;最后,通过干涉条纹的变化,即可感知到引入相位的大小,继而推出位移的变化量,因此也就获得了加速度的大小.该加速度计的优点:SRS过程中产生的斯托克斯光场和对应产生的原子自旋波相位是相互关联的,从而保障了装置中相位的稳定性;该装置简单,测量范围可调,增加了其适用的范围;同时,理想情况下,其精度能超越标准量子极限(Standard Quantum Limit,SQL).

In this paper,we present a new type of atom-light accelerometer(ALA)based on use of an atomlight hybrid interferometer.At present,all-optical accelerometers are the most commonly used and most stable accelerometers on the market,owing to their small size and high accuracy.However,due to measurement bandwidth limitations,their practical application range is limited.Hence,we designed a new type of accelerometer to address this challenge.The atom-light hybrid interferometer is first constructed in the atomic system through the stimulated Raman scattering(SRS)process,and the elastic mass of the accelerometer is formed by a mirror.When the mass is subjected to acceleration on the experimental platform,it will perceive the change in external displacement,thereby introducing the phase into the interferometer.Through the change of the interference fringe,the change of the external phase and the displacement can be determined;hence,the magnitude of the acceleration can be obtained.The primary advantage of the atom-light accelerometer is that the Stokes field generated by the SRS process is phase related to the atomic spin-wave,which ensures the stability of the device phase.Secondly,the adjustable bandwidth of the device increases its scope of application.Finally,theoretical calculations show that its measurement accuracy exceeds the standard quantum limit(SQL)under ideal conditions.