Phase-coupled simultaneous coherent perfect absorption and controllable hot-electron photodetection in Schottky junction metamaterial

AbstractWe report a new type of coherent perfect absorption that is determined by the phase coupling between metaatoms and is referred to as the phase-coupled simultaneous coherent perfect absorption (PC-SCPA) for antisymmetric and symmetric incidences and especially the PC-SCPA for antisymmetric and symmetric incidences can be simultaneously achieved in the same bi-layered Schottky junction metamaterial possessing the phase coupling. Our proposed mechanism exploits the phase coupling between metaatoms, which is in contrast with the existing mechanism which depends on the near-field coupling. The theory of PC-SCPA is provided using coupled mode theory with the phase coupling. The operating wavelengths of PC-SCPA are insensitive to the variations of the spacing distances between metaatoms in the lateral and vertical directions. An infrared PC-SCPA-based hot-electron photodetection with dynamically switchable operating wavelengths and dynamically tunable bandwidth is theoretically and numerically verified in the same bi-layered Schottky junction metamaterial. The peak of spectrum of responsivity for antisymmetric and symmetric incidences can be switched to the same wavelength only by altering the phase coupling. Our study may build the bridge among the new type of PC-SCPA, metamaterial, and hot electron and may find potential and significant applications in hot-electron photodetection.

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Collective photonic response of high refractive index dielectric metasurfaces

Scientific Reports ◽

10.1038/s41598-020-72675-3 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Sushanth Reddy Amanaganti ◽

Miha Ravnik ◽

Jayasri Dontabhaktuni

Keyword(s):

Refractive Index ◽

Computer Modelling ◽

Near Field ◽

High Refractive Index ◽

Tuning Parameter ◽

Far Field ◽

Strong Suppression ◽

Perfect Absorption ◽

Field Coupling ◽

Multipole Analysis

Abstract Sub-wavelength periodic nanostructures give rise to interesting optical phenomena like effective refractive index, perfect absorption, cloaking, etc. However, such structures are usually metallic which results in high dissipative losses and limitations for use; therefore, dielectric nanostructures are increasingly considered as a strong alternative to plasmonic (metallic) materials. In this work, we show light-matter interaction in a high refractive index dielectric metasurface consisting of an array of cubic dielectric nano-structures made of very high refractive index material, Te in air, using computer modelling. We observe a distinct band-like structure in both transmission and reflection spectra resulting from the near-field coupling of the field modes from neighboring dielectric structures followed by a sharp peak in the transmission at higher frequencies. From the spatial distribution of the electric and magnetic fields and a detailed multipole analysis in both spherical harmonics and Cartesian components, the dominant resonant modes are identified to be electric and magnetic dipoles. Specifically at lower frequency (60 THz) a novel anapole-like state characterized by strong-suppression in reflection and absorption is observed, reported very recently as ‘lattice-invisibility’ state. Differently, at higher frequency (62 THz), strong absorption and near-zero far field scattering are observed, which combined with the field profiles and the multipole analysis of the near-fields indicate the excitation of an anapole. Notably the observed novel modes occur in the simple geometry of dielectric cubes and are a result of collective response of the metasurfaces. Periodicity of the cubic metasurface is shown as the significant material tuning parameter, allowing for the near-field and far-field coupling effects of anapole metasurface. More generally, our work is a contribution towards developing far-fetching applications based on metamaterials such as integrated devices and waveguides consisting of non-radiating modes.

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Manifestation of the spontaneous parity-time symmetry breaking phase transition in hot-electron photodetection based on a tri-layered metamaterial

Nanophotonics ◽

10.1515/nanoph-2018-0207 ◽

2019 ◽

Vol 8 (3) ◽

pp. 495-504 ◽

Cited By ~ 1

Author(s):

Qiang Bai

Keyword(s):

Phase Transition ◽

Theoretical Model ◽

Symmetry Breaking ◽

Pt Symmetry ◽

Coupled Mode Theory ◽

Hot Electron ◽

Electron Device ◽

Coupled Mode ◽

Time Symmetry ◽

Existence Conditions

AbstractWe theoretically and numerically demonstrate that the spontaneous parity-time (PT) symmetry breaking phase transition can be realized respectively by using two independent tuning ways in a tri-layered metamaterial that consists of periodic array of metal-semiconductor Schottky junctions. The existence conditions of PT symmetry and its phase transition are obtained by using a theoretical model based on the coupled mode theory. A hot-electron photodetection based on the same tri-layered metamaterial is proposed, which can directly show the spontaneous PT symmetry breaking phase transition in photocurrent and possesses dynamical tunability and switchability. This work extends the concept of PT symmetry into the hot-electron photodetection, enriches the functionality of the metamaterial and the hot-electron device, and has varieties of potential and important applications in optoelectronics, photodetection, photovoltaics, and photocatalytics.

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Schottky-Junction-based Near-Infrared Sub-Bandgap Organic Photodetectors with Coherent Perfect Absorption

Conference on Lasers and Electro-Optics ◽

10.1364/cleo_si.2020.sm3r.7 ◽

2020 ◽

Author(s):

Yeonghoon Jin ◽

Hyung Suk Kim ◽

Seunghyup Yoo ◽

Kyoungsik Yu

Keyword(s):

Near Infrared ◽

Schottky Junction ◽

Perfect Absorption ◽

Coherent Perfect Absorption ◽

Organic Photodetectors

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An ab-initio coupled mode theory for near field radiative thermal transfer

Optics Express ◽

10.1364/oe.22.030032 ◽

2014 ◽

Vol 22 (24) ◽

pp. 30032 ◽

Cited By ~ 11

Author(s):

Hamidreza Chalabi ◽

Erez Hasman ◽

Mark L. Brongersma

Keyword(s):

Ab Initio ◽

Near Field ◽

Coupled Mode Theory ◽

Mode Theory ◽

Coupled Mode ◽

Thermal Transfer

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Low-threshold lasing in a plasmonic laser using nanoplate InGaN/GaN

Journal of Semiconductors ◽

10.1088/1674-4926/42/12/122803 ◽

2021 ◽

Vol 42 (12) ◽

pp. 122803

Author(s):

Ting Zhi ◽

Tao Tao ◽

Xiaoyan Liu ◽

Junjun Xue ◽

Jin Wang ◽

...

Keyword(s):

Data Storage ◽

Near Field ◽

Lasing Threshold ◽

High Loss ◽

Field Coupling ◽

Ohmic Losses ◽

New Type ◽

Refractive Index Material ◽

Low Threshold ◽

Plasmonic Nanolaser

Abstract Plasmonic nanolaser as a new type of ultra-small laser, has gain wide interests due to its breaking diffraction limit of light and fast carrier dynamics characters. Normally, the main problem that need to be solved for plasmonic nanolaser is high loss induced by optical and ohmic losses, which leads to the low quality factor. In this work, InGaN/GaN nanoplate plasmonic nanolaser with large interface area were designed and fabricated, where the overlap between SPs and excitons can be enhanced. The lasing threshold is calculated to be ~6.36 kW/cm2, where the full width at half maximum (FWHM) drops from 27 to 4 nm. And the fast decay time at 502 nm (sharp peak of stimulated lasing) is estimated to be 0.42 ns. Enhanced lasing characters are mainly attributed to the strong confinement of electromagnetic wave in the low refractive index material, which improve the near field coupling between SPs and excitons. Such plasmonic laser should be useful in data storage applications, biological application, light communication, especially for optoelectronic devices integrated into a system on a chip.

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COUPLED-MODE PREDICTION OF BACKSCATTER

Journal of Computational Acoustics ◽

10.1142/s0218396x03002103 ◽

2003 ◽

Vol 11 (04) ◽

pp. 551-561 ◽

Cited By ~ 1

Author(s):

SUZANNE T. MCDANIEL

Keyword(s):

Near Field ◽

Lower Boundary ◽

Coupled Mode Theory ◽

Ideal Boundary ◽

Lower Boundary Condition ◽

Careful Choice ◽

Mode Theory ◽

Coupled Mode ◽

Layered Waveguide ◽

Grazing Angles

The application of coupled-mode theory to ocean acoustic propagation and scattering requires that ideal boundary conditions be applied at the surface and within the seabed. The depth of the lower boundary imposes limits on the ability of coupled-mode models to treat propagation and scattering at high grazing angles. Selecting this depth to predict the contributions of the continuous spectrum in a range-independent two-layered waveguide is not practical, and other methods must be introduced to apply coupled-mode theory in the near field of a source. An example of up-slope propagation in a range-dependent waveguide in which backscatter is governed by ray steepening and reversal is also treated. With a careful choice of the depth at which the lower boundary condition is applied, an estimate of the backscattered field is obtained.

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