Fig. 1. Illustration of a patch antenna. The figure shows the simulated vertical component of the distribution of the electric field Ez in the dielectric area. The impedance mismatch between the single-metal and double-metal regions leads to a lateral Fabry–Perot effect and hence the formation of the standing wave pattern.

Fig. 2. (a) Scanning electron microscope image of the detector, with partial enlargements of the electrically connected patch antennas. The main parameters of the array are indicated in the diagram. Region A: the photonic collection area. Region B: the top metal electrode for the 10.0-μm channel. Region C: the top metal electrode for the 5.7-μm channel. Region D: the bottom metal electrode. Region E: SiO2 for electrical insulation. Region F: the Ti/Au ground plane. (b) Conduction band diagram and relevant energy levels of one period active core. The shaded wells are Si doped, and the optical transitions are indicated by the black arrows.

Fig. 3. (a) Respectively normalized simulated distribution of the absolute vertical component of the electric field |Ez| at the center plane of the active region. The wavelengths and polarization directions of the incident light are indicated in the figure. (b) Simulated reflectivity spectrum of the devices.

Fig. 4. (a) Normalized responsivity spectrum of the device at 77 K and zero bias, in the case of unpolarized incident light. (b) Peak responsivity of the device as a function of temperature. (c) Detectivity of the device as a function of temperature. From left to right, the device works in dual-color, long-wave, and mid-wave modes sequentially.

Fig. 5. (a) Normalized responsivity spectrum of the detector as a function of the polarization angle of the incident light, at 77 K and zero bias. (b) Peak responsivity as a function of the polarization angle, at 77 K and zero bias. From left to right, the device works in dual-color, long-wave, and mid-wave modes, respectively.

Fig. 6. Ratio of the peak responsivity of the two channels as a function of the polarization angle.

Fig. 7. Partial enlargement of the electrically connected patch antennas of the “Patch-Parallel” device.

Fig. 8. Peak responsivity of the “Patch-Parallel” device as a function of the polarization angle, at 77 K and zero bias. From left to right, the device works in dual-color, long-wave, and mid-wave modes, respectively.

Fig. 9. Ratio of the peak responsivity of the “Patch-Parallel” device of the two channels as a function of the polarization angle.