Thermo-optical phase shifter, Mazehnder interferometer and optical computing network

The utility model discloses a thermo-optical phase shifter, a Marzehnder interferometer and an optical computing network. The thermo-optical phase shifter comprises a lithium niobate waveguide layer, a coating layer, a heating piece and a heat insulation groove; the coating layer covers the periphery of the lithium niobate waveguide layer, and the refractive index of the coating layer is smaller than that of the lithium niobate waveguide layer; the heating piece is arranged on the coating layer; the heat insulation grooves are formed in the coating layer and located in the side faces of the heating piece and the lithium niobate waveguide layer. The lithium niobate waveguide layer is heated by using the heating piece, so that the temperature of the lithium niobate waveguide layer can be increased, the refractive index of the lithium niobate waveguide layer is further adjusted, and the phase of light waves transmitted in the thermo-optic phase shifter is adjusted. The heat insulation grooves are formed in the c