## 3 Results and Discussion
In order to further investigate the physical mechanisms of the metamaterial absorber, the electric field distribution in the z plane of the top-layer microstructure at the near-perfect absorption point of the absorber was studied when the conductivity of VO\({}_{2}\) is set to 200 S/m, 20,000 S/m, 80,000 S/m, and 200,000 S/m, as shown in Figure 4. It is evident that at a conductivity of 200 S/m, VO\({}_{2}\) remains in an insulating phase, resulting in minimal electric field distribution on the resonant layer. This leads to terahertz waves easily penetrating through the resonant layer, resulting in a relatively minimal absorption. As the conductivity of VO\({}_{2}\) increases, the electric field tends to focus within the voids of the VO\({}_{2}\) design. Upon achieving an electrical conductivity of 200,000 S/m, there is a noticeable emergence of the electric field distribution surrounding the annulus. This leads to an increased influence of the resonating and reflecting layers on terahertz waves, resulting in a higher level of absorption. VO\({}_{2}\) exhibits sensitivity to variations in temperature, allowing for indirect control of its conductivity through temperature adjustments, resulting in a dynamic tuning capability for wideband absorbers. This feature is not attainable with conventional metal-based absorbers. Broadband absorbers utilizing VO\({}_{2}\) have the capability to switch actively between absorption and reflection, with the added feature of dynamic regulation through temperature management. This opens up new avenues for exploration in the realm of multifunctional THz devices. In order to fully understand the influence of absorber structural parameters on its absorption characteristics, a detailed study was conducted on the absorption spectrum of the absorber structure under different parameters. Figure 3: Absorption rate and relative impedance of the absorber under different conditions. (**a**,**b**) VO\({}_{2}\) in metallic phase and (**c**,**d**) VO\({}_{2}\) in insulating phase. Figure 5a shows that there is a decrease in absorption observed at the 5 THz frequency for the absorber as the size \(\mathrm{r_{1}}\) increases. There is hardly any alteration observed in the absorption profile as the dimension \(\mathrm{r_{2}}\) is raised. This phenomenon is a result of the gradual reduction in the strength of the electric field at the outer perimeter of the ring when \(\mathrm{r_{1}}\) is adjusted, thereby diminishing the absorber's reaction to incident THz waves and causing a drop in absorption. In contrast, modifications in \(\mathrm{r_{2}}\) do not impact the electric field strength at the outer edge of the ring. By examining the electric field discussed previously, it is evident that alterations in the electric field's intensity are more pronounced at the perimeter of the circular structure. In contrast, during the insulating phase of VO\({}_{2}\), there is minimal distribution of the electric field within the VO\({}_{2}\) layer. Therefore, modifying the dimensions of the loop using either \(\mathrm{r_{1}}\) (the outer radius of the VO\({}_{2}\) ring) or \(\mathrm{r_{2}}\) (the inner radius of the VO\({}_{2}\) ring) does not exert a significant influence on the absorption rate due to the low sensitivity of the absorber configuration to THz waves. From Figure 5, it can also be seen that when the values of \(\mathrm{r_{1}}\) or \(\mathrm{r_{2}}\) are changed, a small absorption peak appears near 9.6 THz. This may be due to the fact that when VO\({}_{2}\) is in an insulating state, its band structure becomes more separated, resulting in a significant enhancement of light absorption within a specific wavelength range. Figure 4: Electric field distribution under different conductivity. (**a**) 200 S/m; (**b**) 20,000 S/m; (**c**) 80,000 S/m; (**d**) 200,000 S/m. Figure 5: _Cont._  
Exploring the impact of varying polarization and incident angles on the absorber's absorption capabilities holds significant importance.