Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userElectromagnetic Field Enhancement in Bloch Surface Waves
183
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
We present a systematic comparison between guided modes supported by slab waveguides and Bloch Surface Waves (BSWs) propagating at the surface of truncated periodic multilayers. We show that, contrary to common belief, the best surface field enhancement achievable for guided modes in a slab waveguide is comparable to that observed for BSWs. At the same time, we demonstrate that, if one is interested in maximizing the electromagnetic energy density at a generic point of a dielectric planar structure, BSWs are often preferable to modes in which light is confined uniquely by total internal reflection. Since these results are wavelength independent and have been obtained by considering a very wide range of refractive indices of the structure constituent materials, we believe they can prove helpful in the design of future structures for the control and the enhancement of the light-matter interaction.
rate research
Read More
A few recent works suggest the possibility of controlling light propagation at the interface of periodic multilayers supporting Bloch surface waves (BSWs), but optical resonators based on BSWs are yet to demonstrate. Here we discuss the feasibility of exploiting guided BSWs in a ring resonator configuration. In particular, we investigate the main issues related to the design of these structures, and we discuss about their limitations in terms of quality factors and dimensions. We believe these results might be useful for the development of a complete BSW-based platform for application ranging from optical sensing to the study of the light-matter interaction in micro and nano structures.
We theoretically study light propagation in guided Bloch surface waves (BSWs) supported by photonic crystal ridges. We demonstrate that low propagation losses can be achieved just by a proper design of the multilayer to obtain photonic band gaps for both light polarizations. We present a design strategy based on a Fourier analysis that allows one to obtain intrinsic losses as low as 5 dB/km for a structure operating in the visible spectral range. These results clarify the limiting factors to light propagation in guided BSWs and represent a fundamental step towards the development of BSW-based integrated optical platforms.
The propagation of electromagnetic surface waves guided by the planar interface of two isotropic chiral materials, namely materials $calA$ and $calB$, was investigated by numerically solving the associated canonical boundary-value problem. Isotropic chiral material $calB$ was modeled as a homogenized composite material, arising from the homogenization of an isotropic chiral component material and an isotropic achiral, nonmagnetic, component material characterized by the relative permittivity $eps_a^calB$. Changes in the nature of the surface waves were explored as the volume fraction $f_a^calB$ of the achiral component material varied. Surface waves are supported only for certain ranges of $f_a^calB$; within these ranges only one surface wave, characterized by its relative wavenumber $q$, is supported at each value of $f_a^calB$. For $mbox{Re} lec eps_a^calB ric > 0 $, as $left| mbox{Im} lec eps_a^calB ric right|$ increases surface waves are supported for larger ranges of $f_a^calB$ and $left| mbox{Im} lec q ric right|$ for these surface waves increases. For $mbox{Re} lec eps_a^calB ric < 0 $, as $ mbox{Im} lec eps_a^calB ric $ increases the ranges of $f_a^calB$ that support surface-wave propagation are almost unchanged but $ mbox{Im} lec q ric $ for these surface waves decreases. The surface waves supported when $mbox{Re} lec eps_a^calB ric < 0 $ may be regarded as akin to surface-plasmon-polariton waves, but those supported for when $mbox{Re} lec eps_a^calB ric > 0 $ may not.
Nonlinear optical media that are normally dispersive, support a new type of localized (nondiffractive and nondispersive) wavepackets that are X-shaped in space and time and have slower than exponential decay. High-intensity X-waves, unlike linear ones, can be formed spontaneously through a trigger mechanism of conical emission, thus playing an important role in experiments.
We show that, contrary to the common wisdom, surface plasmon poles are not involved in the imaging process in leakage radiation microscopy. Identifying the leakage radiation modes directly from a transverse magnetic potential leads us to reconsider the surface plasmon field and unfold the non-plasmonic contribution to the image formation. While both contributions interfere in the imaging process, our analysis reveals that the reassessed plasmonic field embodies a pole mathematically similar to the usual surface plasmon pole. This removes a long-standing ambiguity associated with plasmonic signals in leakage radiation microscopy.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
