Journal of Physics Communications
Improvement of angular rotation measurement resolution and sensitivity based on an SU(1,1) interferometer with intensity sum detection
Yuanxiang Wang, Shuzhen Li, Youyou Hu, Mingming Zhang, Jun Liu
Abstract
Abstract In order to realize the enhancement of angular rotation measurement sensitivity, a new scheme based on an SU(1,1) interferometer with intensity sum detection has been proposed. A coherent beam carrying orbital angular momentum (OAM) enters into the SU(1,1) interferometer where the Dove prisms are inserted. By taking full advantage of the two outports and employing intensity sum detection, the angular rotation measurement sensitivity can be enhanced by higher gain, photon number and OAM. Meanwhile, resolution can be improved while the pump beam carries OAM. The angular rotation measurement sensitivity of the SU(1,1) interferometer can beat standard quantum limit 1 / ( 2 l N ), and it still can be optimal when photon depletion inside this interferometer is the same.