Theoretical investigation of a controlled unidirectional reflectionlessness by applying external voltage in an electro-optical plasmonic waveguide system

Abstract

We theoretically investigate an controlled unidirectional reflectionlessness and near perfect absorption by applying external voltage in an electro-optical plasmonic waveguide system based on near-field coupling between two resonators. The system consists of two resonators side coupled to a metal-dielectric-metal plasmonic waveguide. Based on the numerical simulation, when external voltage is U = 7.4 V, the reflections for forward and backward directions are close to 0 and 0.82 at frequency 144.18 THz, while the reflections for forward and backward directions are close to 0.81 and 0 at frequency 150.86 THz when external voltage is U = 1.5 V. And the high absorption for forward (backward) direction is ∼0.97 (∼0.99) at frequency 144.18 THz (150.86 THz).

Selective Light Absorption and Spectral Manipulation via an Electro-Optical Nano-Cavity

“…The ITO is set to be 1.45. As for the DAST material [37], [40], [41], the refractive index is associated with the external voltage U with the function:…”

“…Moreover, the DAST is with outstanding electro-optic and nonlinear optical properties [30], [31]. Recently, both the organic and inorganic nonlinear optical materials were widely used for the investigations in nonlinear optics [32]- [34] and electro-optic modulator [35]- [37]. Although the strong nonlinear optics and electro-optical effects for these materials have been studied, the feasible way to manipulate the light absorption of the metamaterial absorber with a high performance has not been well established.…”

Unidirectional Reflectionlessness and Transmissionlessness in Indirectly Coupled Whispering‐Gallery Mode Resonators

“…[35] In 2022, Zhou et al have studied nonreciprocal optical transmission in a spinning resonator system coupled to an atomic ensemble. [40] The aforementioned investigations mainly focused on transmission characteristics, whereas optical devices based on the mechanism of unidirectional reflectionlessness (UR) [41][42][43] can not only protect upper stage optical devices from reflected light in the cascade circuit to improve system stability, but also convey information, similar to transmission. Up to now, UR has demonstrated the significant potential applications in sensors, diodes, isolators, filters, and so on, and thus research on UR continues to grow.…”