# sf.decompositions.M¶

M(n, sigma, delta, m)[source]

The symmetric Mach Zehnder interferometer matrix. (Eq 1 of the paper (arXiv:2104.0756).)

Parameters
• n (int) – the starting mode of sMZI

• sigma (complex) – parameter of the sMZI $$\frac{(\theta_1+\theta_2)}{2}$$, where $$\theta_{1,2}$$ are the values of the two internal phase-shifts of sMZI

• delta (complex) – parameter of the sMZI $$\frac{(\theta_1-\theta_2)}{2}$$, where $$\theta_{1,2}$$ are the values of the two internal phase-shifts of sMZI

• m (int) – the length of the unitary matrix to be decomposed

Returns

the sMZI matrix between n-th and (n+1)-th mode

Return type

array[complex,complex]