We have studied the scattering of bi-photon input pulses from a six-port interferometer given by 3x3 unitary matrix, with different coincidences at the three output ports. The distinguishability of photons is introduced by taking time delays in the input. We observe different patterns of dips and peaks in coincidence probabilities by varying the time delays, manifesting destructive and constructive interference. The coincidence probability comes out to be octic function of the elements of scattering matrix U 3 and provides a means to learn matrix elements. This study provides insight into the interferometric properties of two independent photons in the same port. This is specifically useful in the case of chips where geometry of the chip forces photons in the same spatial input port.

中文翻译：

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多模双光子输入脉冲的量子干涉法

我们研究了由3x3 ary矩阵给出的六端口干涉仪产生的双光子输入脉冲的散射，这三个输出端口的重合度不同。通过考虑输入中的时间延迟来引入光子的可区分性。通过改变时间延迟，我们观察到重合概率不同的波峰和波峰模式，表现出破坏性和建设性的干扰。符合概率成为散射矩阵U 3的元素的八次函数，并提供了学习矩阵元素的方法。这项研究深入了解了同一端口中两个独立光子的干涉特性。这对于芯片的几何形状迫使光子进入同一空间输入端口的芯片特别有用。