Polarization-independent and angle-insensitive electromagnetically induced transparent (EIT) metamaterial based on bi-air-hole dielectric resonators

Abstract

We numerically demonstrate that an electromagnetically induced transparent (EIT) all-dielectric metamaterial with properties of polarization-independence and incident angle insensitivity can be achieved in terahertz regimes. The metamaterial cell is composed of two bi-air-hole cubes (BCs) with different sizes. The two BCs function as superradiant and subradiant resonators, respectively. Based on Mie-type destructive interferences between dielectric resonators, the EIT effect is induced at around 8.25 THz with the transmission peak close to 0.95. Moreover, the "two-particle" model is introduced to describe the EIT effect and the influence of couplings between the two BCs on the transmission spectra.Analytical results are in good agreement with numerical simulation results. Owing to the symmetry and uniformity of the metamaterial structure, polarization-independent and angle-insensitive properties can be achieved. In addition, the slow light characteristic of the metamaterial is also verified. Such an EIT scheme may have potential applications in low-loss slow light devices and bandpass filters.

Dual Tunable Electromagnetically Induced Transparency Based on a Grating-Assisted Double-Layer Graphene Hybrid Structure at Terahertz Frequencies

“…The slow-light effect is an important phenomenon in EIT-like devices, and the performance is mainly measured by the group delay ( ) and group refractive index ( ), both of which are determined by the following formulae [ 28 , 29 , 30 ]: where , , , and are the transmission phase, angular frequency, light velocity in the vacuum, and the total thickness of the unit cell, respectively. The curves of the phase and group delay obtained from the present structure as a function of frequency during the growth of the graphene chemical potential from 0.6 eV to 0.7 eV in 0.025 eV increments are given in Figure 6 a–e, and it is known that the present device is capable of achieving a stable 0.6 ps group delay within the proposed chemical potential interval.…”

Design of Broadband Plasmon‐Induced Transparency Hybrid Metamaterial Based on the Interaction of the Metal and Dielectric Resonances

“…The similar distributions can also be confirmed by the vector plot of the magnetic field, which is presented in the Supporting Information and clearly shows that two symmetrical vectors circulations of the magnetic field are clearly formed on both sides of the TiO 2 NBSRs, corresponding to the feature of the 1-order Mie magnetic resonances. [67] So that a resonant frequency with strong contrasting Q factors but small frequency detuning is produced at 0.75 THz compared to the bright resonance in Figure 2a. The Q factors of basic resonance modes are calculated as below and listed in Table 2.…”

“…The similar distributions can also be confirmed by the vector plot of the magnetic field, which is presented in the Supporting Information and clearly shows that two symmetrical vectors circulations of the magnetic field are clearly formed on both sides of the TiO 2 NBSRs, corresponding to the feature of the 1‐order Mie magnetic resonances. [ 67 ]…”

Polarization-independent analog of electromagnetically induced transparency based on longitudinal and transverse mode coupling

“…To obtain polarization-independent EIT-like devices, many complex structures have been designed 8 , 23 – 27 However, these structures, such as other polarization-sensitive EIT-like devices, still use the coupling effect between the transverse resonance modes to obtain the EIT effect. In fact, optical metamaterial devices not only have transverse resonance modes but also can obtain EIT-like effects using longitudinal modes 7 …”