scholarly journals Complex Analysis of Emission Properties of LEDs with 1D and 2D PhC Patterned by EBL

Coatings ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 748
Author(s):  
Lubos Suslik ◽  
Jaroslava Skriniarova ◽  
Jaroslav Kovac ◽  
Dusan Pudis ◽  
Anton Kuzma ◽  
...  

In this paper, we present the optical and electrical properties of surface-patterned GaAs-based Multiquantum Well (MQW) light emitting diodes (LEDs) with one- and two-dimensional photonic crystal (PhC) structures. Optical properties were analyzed in the near and far field, measured by a near-field scanning optical microscope and with a goniophotometer. We demonstrated a strong effect of patterned PhC on the radiation properties and the light extraction efficiency. Enormous surface emission enhancement reaching 110% confirmed the strong effect of the patterned structure on the coupling of the guided modes into the surface emission. Additionally, the considerable effect of the PhC structure diffraction on radiation pattern was confirmed in the near and far field and is in good agreement with the simulated shape of the optical field.

Open Physics ◽  
2010 ◽  
Vol 8 (3) ◽  
Author(s):  
Petr Klapetek ◽  
Juraj Bujdák ◽  
Jiří Buršík

AbstractThis article presents results of near-field scanning optical microscope measurement of local luminescence of rhodamine 3B intercalated in montmorillonite samples. We focus on how local topography affects both the excitation and luminescence signals and resulting optical artifacts. The Finite Difference in Time Domain method (FDTD) is used to model the electromagnetic field distribution of the full tip-sample geometry including far-field radiation. Even complex problems like localized luminescence can be simulated computationally using FDTD and these simulations can be used to separate the luminescence signal from topographic artifacts.


2021 ◽  
Vol 2021 ◽  
pp. 1-22
Author(s):  
Zhenyuan Lin ◽  
Minghui Hong

As a noncontact strategy with flexible tools and high efficiency, laser precision engineering is a significant advanced processing way for high-quality micro-/nanostructure fabrication, especially to achieve novel functional photoelectric structures and devices. For the microscale creation, several femtosecond laser fabrication methods, including multiphoton absorption, laser-induced plasma-assisted ablation, and incubation effect have been developed. Meanwhile, the femtosecond laser can be combined with microlens arrays and interference lithography techniques to achieve the structures in submicron scales. Down to nanoscale feature sizes, advanced processing strategies, such as near-field scanning optical microscope, atomic force microscope, and microsphere, are applied in femtosecond laser processing and the minimum nanostructure creation has been pushed down to ~25 nm due to near-field effect. The most fascinating femtosecond laser precision engineering is the possibility of large-area, high-throughput, and far-field nanofabrication. In combination with special strategies, including dual femtosecond laser beam irradiation, ~15 nm nanostructuring can be achieved directly on silicon surfaces in far field and in ambient air. The challenges and perspectives in the femtosecond laser precision engineering are also discussed.


Author(s):  
E. Betzig ◽  
M. Isaacson ◽  
H. Barshatzky ◽  
K. Lin ◽  
A. Lewis

The concept of near field scanning optical microscopy was first described more than thirty years ago1 almost two decades before the validity of the technique was verified experimentally for electromagnetic radiation of 3cm wavelength.2 The extension of the method to the visible region of the spectrum took another decade since it required the development of micropositioning and aperture fabrication on a scale five orders of magnitude smaller than that used for the microwave experiments. Since initial reports on near field optical imaging8-6, there has been a growing effort by ourselves6 and other groups7 to extend the technology and develop the near field scanning optical microscope (NSOM) into a useful tool to complement conventional (i.e., far field) scanning optical microscopy (SOM), scanning electron microscopy (SEM) and scanning tunneling microscopy. In the context of this symposium on “Microscopy Without Lenses”, NSOM can be thought of as an addition to the exploding field of scanned tip microscopy although we did not originally conceive it as such.


Author(s):  
Vladimir Gerasik ◽  
Marek Stastna

A two-dimensional boundary-value problem for a porous half-space with an open boundary, described by the widely recognized Biot's equations of poroelasticity, is considered. Using complex analysis techniques, a general solution is represented as a superposition of contributions from the four different types of motion corresponding to P1, P2, S and Rayleigh waves. Far-field asymptotic solutions for the bulk modes, as well as near-field numerical results, are investigated. Most notably, this analysis reveals the following: (i) a line traction generates three wave trains corresponding to the bulk modes, so that P1, P2 and S modes emerge from corresponding wave trains at a certain distance from the source, (ii) bulk modes propagating along the plane boundary are subjected to geometric attenuation, which is found quantitatively to be x −3/2 , similar to the classical results in perfect elasticity theory, (iii) the Rayleigh wave is found to be predominant at the surface in both the near (due to the negation of the P1 and S wave trains) and the far field (due to geometric attenuation of the bulk modes), and (iv) the recovery of the transition to the classical perfect elasticity asymptotic results validates the asymptotics established herein.


Nanophotonics ◽  
2013 ◽  
Vol 2 (3) ◽  
pp. 173-185 ◽  
Author(s):  
Simona Ungureanu ◽  
Branko Kolaric ◽  
Jianing Chen ◽  
Rainer Hillenbrand ◽  
Renaud A. L. Vallée

AbstractIn this paper, the resonance modes exhibited by a hybrid nanostructure have been disentangled in the far-field owing to narrow-band fluorescence nano-reporters. Hybrid plasmonic-photonic crystals were fabricated using large (457 nm) monodisperse polystyrene spheres self-assembled into 2D photonic crystals and subsequently coated by a 30 nm thick silver layer. Such structures exhibit a complex resonance pattern, which has been elucidated owing to numerical simulations and electric near-field patterns obtained with a scattering type scanning near-field optical microscope (s-SNOM). For the sake of disentangling the resonance modes of the hybrid structure in the far-field, different types of semiconductor quantum dots (QDs), acting as nano-reporters of the local interactions, were dispersed on top of distinct structures. Depending on the relative overlap of the emission spectrum of a particular type of QDs with the resonance features of the hybrid structure, we affect their emission rate in a unique way, as a consequence of the complex interaction occurring between the plasmo-photonic modes and the excitons. Such plasmonic structures appear to be particularly relevant for fluorescence-based sensing devices.


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