Fig. 3: Experimental demonstration of the tunable two-mode braiding building block.
a Measured output light intensity images of a structure featuring only step I with a laser of 1550 nm injected from the waveguide A, when the electrode heaters are turned off (upper panel) and on (lower panel). b Measured output light intensity images of a step II structure, where the input is from the waveguide B with electrodes turned off (upper panel), from the waveguide B (middle panel), or A (lower panel) with electrodes turned on. c Measured output images of step III, where light is injected from the waveguide S with electrodes turned off (upper panel) and from the waveguide B with electrodes turned on (lower panel). d Measured output light intensity images of the two-mode braiding structure when the electrode heaters are turned off (left column) and on (right column). In (a–d), the red arrows mark the waveguide in which light is injected. Measured transmission coefficients TA,A, TB,A, TA,B, and TB,B (see main text for definition) in the two-mode braiding building block as a function of wavelengths when the electrode heaters are turned off (e) and on (f).
