Fig. 6: The analysis of the optical response properties of the dual-layer waveguide device with 405 nm wavelength pumping light excitation.

a The top-view microscope when coupling 532 and 655 nm signal lights with 405 nm wavelength light pumping in; b the output optical fields of both signal sources (×50); (c) and (d) are the curves of relative gain versus pumping light power intensity variation for 532 and 655 nm wavelength signal source; (e) and (f) are the input/output response square-wave with pulse-code modulation for 532 nm wavelength signal source at a frequency of 250 Hz; (g) and (h) are the input/output response square-wave with pulse-code modulation for 655 nm wavelength signal source at a frequency of 250 Hz.