Fig. 1. Schematic diagram of the structure of the breaking arm MZI, consisting of two directional couplers with a splitting ratio of 1∶1 and a breaking line waveguide. IN1 is the laser input port, OUT1 and OUT2 are the two output ports

Fig. 2. (a) Model of Gaussian beam propagation in a disconnected waveguide; (b) Light field distribution of Gaussian beam propagation in waveguides with different breaking

Fig. 3. (a) Beam waist radius versus propagation distance L for different background refractive indices at w₀=4 μm; (b) Simulated mode field distribution of Gaussian light diverging inside a material with refractive index n2

Fig. 4. (a) Theoretical simulation of disconnected waveguide loss versus breaking length L; (b) Experimentally measured disconnected waveguide loss versus breaking length L, the inset is a microscope image of the waveguide end face

Fig. 5. Simulated optical field of a breaking arm MZI device

Fig. 6. Measured and simulated histogram of MZI transmission