Plasmon-induced transparency effect for ultracompact on-chip devices

Abstract

On-chip plasmon-induced transparency (PIT) possessing the unique properties of controlling light propagation states is a promising way to on-chip ultrafast optical connection networks as well as integrated optical processing chips. On-chip PIT has attracted enormous research interests, the latest developments of which have also yield progress in nanophotonics, material science, nonlinear optics, and so on. This review summarizes the realization methods, novel configurations, diversiform materials, and the improved performance indexes. Finally, a brief outlook on the remaining challenges and possible development direction in the pursuit of the application of a practical on-chip photonic processor based on PIT is also afforded.

Fano Resonance in Artificial Photonic Molecules

“…Ohmic losses, which decrease the sharpness of Fano profile, continue to hinder the applications of plasmonic–photonic molecules. [ 83,86–88 ] Parity‐time symmetry may provide a new degree of freedom for creating novel plasmonic functional devices, and the loss in plasmonic structure can be compensated by the gain medium. [ 83,126,155,156 ] The gain, loss and interplay between the elements play essential roles in realizing PT symmetric photonic structure.…”

“…Figure 1c shows a three‐level atomic system, where |1〉, |2〉, and |3〉 correspond to the ground state, metastable state and excited state, respectively. [ 87 ] Due to the probe field and control field, the ground state and metastable state couple to the excited state, thus the transitions |1〉→|3〉 and |2〉→|3〉 are allowed while the transition |1〉→|2〉 is forbidden. To realize an atom in the excited state, there are the direct transition path |1〉→|3〉 and indirect transition path |1〉→|3〉→|2〉→|3〉.…”

“…It is well‐known that the macroscopically arrayed structures are typically too bulky for highly integrated on‐chip optical circuits, thus, compact photonic structures are in high demand. [ 83–85 ] Optical microcavities, with high quality (high‐Q) factors, convenient all‐optical control, and compatibility with on‐chip fabrication, have been used extensively for sophisticated optical devices, such as isolators, [ 86 ] lasers, [ 87 ] circuits, [ 88 ] sensors, [ 89–91 ] and buffers, [ 92,93 ] with distinctive properties. Based on the similarities between the classical electromagnetism and quantum mechanics, a single cavity and coupled‐cavity can be referred to as artificial photonic atom and photonic molecule, [ 94–96 ] respectively.…”

Anapole-assisted giant electric field enhancement for surface-enhanced coherent anti-Stokes Raman spectroscopy

“…Breaking the geometrical symmetry 18 – 21 , heterogeneous configuration 22 – 24 , structural nano-assembly 25 , phase retardation 26 , and the polarization direction of the incident light 27 are the most important parameters which can enable efficient excitation of the dark modes and hybridization of plasmons of different multipolar symmetry. The narrower spectral linewidth compared to the standard plasmon resonances as well as the large local field enhancement provided by the dark modes, make the plasmonic Fano-based structures an ideal platform for diverse applications such as refractive index chemical and biological sensing 24 , 28 – 30 , surface-enhanced spectroscopy 31 , 32 , low-threshold nano-lasers 33 , and novel on-chip photonic device designs 34 , 35 .…”

Dual-Spectral Plasmon-Induced Transparent Terahertz Metamaterial with Independently Tunable Amplitude and Frequency

“…Previous studies have shown that PIT effect can be achieved mainly via bright and bright mode, bright and dark mode, and bright and quasi-dark mode [9][10][11][12]. At a PIT peak region, strong dispersion can occur, causing slow light effect which can be used in optical information processing [13][14][15][16].…”