Michael Yoad, Jonas Isaac, Bello Leon, Meller Mallachi-Ellia, Cohen Eliahu, Rosenbluh Michael, Pe'er Avi
BINA Center for Nanotechnology, Bar-Ilan University, Ramat Gan, 5290002, Israel.
Phys Rev Lett. 2021 Oct 22;127(17):173603. doi: 10.1103/PhysRevLett.127.173603.
We analyze theoretically and experimentally cases of asymmetric detection, stimulation, and loss within a quantum nonlinear interferometer of entangled pairs. We show that the visibility of the SU(1,1) interference directly discerns between loss on the measured mode (signal) and the conjugated mode (idler). This asymmetry also affects the phase sensitivity of the interferometer, where coherent seeding is shown to mitigate losses that are suffered by the conjugated mode; therefore increasing the maximum threshold of loss that permits sub-shot-noise phase detection. Our findings can improve the performance of setups that rely on direct detection of entangled pairs, such as quantum interferometry and imaging with undetected photons.
我们从理论和实验两方面分析了纠缠对量子非线性干涉仪内的不对称检测、激发和损耗情况。我们表明，SU(1,1)干涉的可见度可直接区分测量模式（信号）和共轭模式（闲频光）上的损耗。这种不对称性也会影响干涉仪的相位灵敏度，其中相干注入被证明可以减轻共轭模式所遭受的损耗；因此提高了允许进行亚散粒噪声相位检测的最大损耗阈值。我们的研究结果可以改善依赖于直接检测纠缠对的装置的性能，例如量子干涉测量和未检测到光子的成像。
