# Ultrathin Terahertz Dual-Band Perfect Metamaterial Absorber Using Asymmetric Double-Split Rings Resonator

^{1}

^{2}

^{*}

## Abstract

**:**

## 1. Introduction

## 2. Design and Simulation

_{1}= 2 μm, the linewidth of the middle arm W

_{2}= 4 μm, the width of the gaps g = 2 μm and the periodicity of SRRs is 40 μm in the x and y axis, as shown in Figure 1d.

## 3. Results and Discussions

## 4. The Effects of the Width of the Gaps and the Middle Arm

## 5. Conclusions

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

## References

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**Figure 1.**Ultrathin terahertz dual band metamaterial absorber. (

**a**) Side view of the unit cell structure with t

_{1}= 7 μm, t = 0.036 μm; (

**b**) Perspective view of the absorber; (

**c**) The front view of the the unit cell with optimized parameters of L = 36 μm, W

_{1}= 2 μm, W

_{2}= 4 μm, g = 2 μm; (

**d**) Periodic structure of the unit cell with Px = Py = 40 μm.

**Figure 2.**Simulated absorptivity for the split ring resonators (SRRs) with various distance of the gaps away from the center.

**Figure 3.**The resonance frequency (

**a**) and the absorption peak (

**b**) as a function of gaps position at low-frequency.

**Figure 4.**Absorptivity of the single SRR and the double SRRs with $\Delta x$ = 7.5 μm, respectively.

**Figure 6.**Simulated surface induction current at (

**a**) $\Delta x$ = 0; (

**c**) $\Delta x$ = 11 μm at low-frequency and (

**b**) $\Delta x$ = 0 μm; (

**d**) $\Delta x$ = 11 μm at high-frequency respectively.

**Figure 7.**Simulated absorptivity as a function of the frequency for the various width of the gaps, with the gaps displaced 11 μm asymmetrically.

**Figure 8.**Simulated absorptivity as a function of frequency for various widths of the middle arm with the gaps displaced 11 μm asymmetrically.

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**MDPI and ACS Style**

Lu, T.; Zhang, D.; Qiu, P.; Lian, J.; Jing, M.; Yu, B.; Wen, J.
Ultrathin Terahertz Dual-Band Perfect Metamaterial Absorber Using Asymmetric Double-Split Rings Resonator. *Symmetry* **2018**, *10*, 293.
https://doi.org/10.3390/sym10070293

**AMA Style**

Lu T, Zhang D, Qiu P, Lian J, Jing M, Yu B, Wen J.
Ultrathin Terahertz Dual-Band Perfect Metamaterial Absorber Using Asymmetric Double-Split Rings Resonator. *Symmetry*. 2018; 10(7):293.
https://doi.org/10.3390/sym10070293

**Chicago/Turabian Style**

Lu, Taiguo, Dawei Zhang, Peizhen Qiu, Jiqing Lian, Ming Jing, Binbin Yu, and Jing Wen.
2018. "Ultrathin Terahertz Dual-Band Perfect Metamaterial Absorber Using Asymmetric Double-Split Rings Resonator" *Symmetry* 10, no. 7: 293.
https://doi.org/10.3390/sym10070293