The giant enhancement of Fano-type resonance in a gain-assisted silicon slab array

Abstract

Giant resonance enhancement is demonstrated to be due to the Fano interference in a grating waveguide composed of gain-assisted silicon slabs. The Fano mode is characterized by its ultra-narrow asymmetric spectrum, different from that of a pure electric or magnetic dipole. The simulation indicates that a sharp Fano-interfered lineshape is responsible for the giant resonance enhancement featuring the small-gain requirements.

Reflection-type electromagnetically induced transparency analogue in terahertz metamaterials

“…This form of reflectance spectrum is similar to that of the transmission spectrum of the EIT reported elsewhere. [15][16][17][18][19][20] We carry out the full-wave numerical simulations to test the performances of the designed metamaterials using the CST Microwave Studio 2010. Here the gold electric conductivity is The two-dimensional (2D) distributions of the electric field at 0.865 THz for the three samples are shown in Fig.…”

“…Many researchers have proposed different structures of metamaterials by mainly using split-ring resonators (SRRs), cut wires (CWs), and plasmonic waveguides to realize the EIT effect. [2][3][4][5][6][7][8][9][10][11][12][13][14] Following appropriate design rules, [3,4,7,[15][16][17][18][19][20] the prominent EIT phenomenon could be realized in metamaterials by destructive interference between different resonance modes. There are two common methods to manipulate the resonance modes by rationally designing the structure of metamaterials.…”

“…[8][9][10] In most previously designed EIT metamaterials, the char-acteristics of the EIT were usually demonstrated through the transmission spectrum. [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] However, the reflection of EIT, an important physical component the same as the transmission of the EIT, is ignored. In this work, a reflection-type EIT metamaterial functioning in the terahertz (THz) regime is proposed, fabricated, and characterized, which is composed of a dielectric substrate sandwiched with metallic patterns and metallic planes.…”

Identification of Analytical Singularity in a Non‐Plasmonic Nanosensing System

“…On the other hand, non-plasmonic NPs with asymmetric Fano resonances are known to support high Q-factors and potentially address the abovementioned issues. [11] Although gainassisted coupled resonant systems have been reported in many cases, [12][13][14] the underlying physics in relation to lasing singularity as well as its accurate identification has yet to be investigated. Coupled oscillator model, as the most intuitive choice of theoretical framework for Fano resonance, [15] does not consider eigenmodes and thus uncovers little of the physics.…”

The metamaterial analogue of electromagnetically induced transparency by dual-mode excitation of a symmetric resonator

“…The near-field map of a dark mode is characterized in most cases by an electric quadrupole mode or magnetic dipolar mode. [24][25][26][27][28][29] Recently, the EIT-like phenomenon has been demonstrated in a sample constructed by a single, but asymmetric, U-shaped resonator, or by a complex design of multi-resonators with two different U-shaped geometries. [21,23] However, no work has been reported on the EIT-like phenomenon that is obtained from a single symmetric U-shaped resonant metamaterial.…”