In this paper, we propose a nonlinear interferometer based on two-port feedback nondegenerate optical parametric amplification (NITFPA), which employs two linear beam splitters to feed the two output beams of a nondegenerate optical parametric amplifier back to its input ports. By comparing the NITFPA with the SU(1,1) interferometer (SUI), which is another typical nonlinear interferometer, we demonstrate that the NITFPA has its unique advantages in the precision enhancement of the phase estimation. In addition, we demonstrate that the NITFPA is also advantageous over the SUI in the robustness against the losses. Such a NITFPA may find its potential applications in quantum metrology.

在本文中，我们提出了一种基于双端口反馈非退化光学参量放大 (NITFPA) 的非线性干涉仪，它采用两个线性分束器将非退化光学参量放大器的两个输出光束反馈回其输入端口。通过将 NITFPA 与另一种典型的非线性干涉仪 SU(1,1) 干涉仪 (SUI) 进行比较，我们证明了 NITFPA 在提高相位估计精度方面具有独特的优势。此外，我们证明 NITFPA 在对抗损失的鲁棒性方面也优于 SUI。这样的 NITFPA 可能会在量子计量学中找到它的潜在应用。