Questions tagged [metamaterials]
Artificial materials with $\varepsilon$ and $\mu$ not found in nature. The "atoms" are sub-wavelength. Includes negative-index materials, superlenses, split-ring resonators, wire media and backwards wave propagation.
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How to derive the effective permeability for split ring resonator?
in Pendry's 1999 paper "Magnetism from Conductors and Enhanced Nonlinear Phenomena", he give the formula of effective relative permeability $mu_r$ of split ring resonator (SRR) which is one ...
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Can someone tell me why there are two values for the dielectric constant from this website?
I have been looking up at available database that had dielectric constants for metals since I need them for my research and wanted to get an idea of what the values were before I focus on actually ...
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What photonic properties of a subwavelength plasmonic cavity make it generate saturated structural colour in just one layer?
I have a photonics question regarding a paper I am reading. Physics is not my area of study so please be kind :))
https://doi.org/10.1126/sciadv.adf7207
In this paper, the group has fabricated a self-...
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Left-handed antiphotons in negative-index material?
Do “left-handed” antiphotons propagate in negative-index metamaterials?
https://pubs.aip.org/physicstoday/article/57/6/37/914849/Reversing-Light-With-Negative-RefractionMaterials
Some quotes from the ...
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Do EM waves have negative frequency inside negative-index materials?
The speed of light in a vacuum, $c$, is defined as positive.
The refractive index of a material, $n$, can be positive or negative.
The dispersion relation for light inside the material is given by
$$\...
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Why does the real part of permittivity (according to lorentz model) converge to 1 faster in materials with less plasma frequency?
according to Lorentz oscillator model that describes optical responses of materials we get a complex permittivity which its real part is given by
we can see that the real part converges to 1 at high ...
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How does resonance of split ring resonator (SRR) prevent transmission?
I am wondering how interference in a split-ring resonator works. From my understanding, an incoming electromagnetic wave through the split ring will produce an emf + current (Faraday's law of ...
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In order to cool below the ambient air temperature using passive radiative cooling during daytime why is it important to radiate heat into space? [closed]
Why not radiate it instead of the surrounding air, like Air conditioners?
I know an air conditioner does not transfer/dump heat to the outside by radiation, but by phase transformation-specifically ...
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Poynting vector and negative index of refraction
Why are the Poynting vector and the wavevector not pointing in the same direction in negative-index media?
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Could you magnetize and at the same time elactrostatically charge a piece of rusted iron?
Pure iron rust (i.e. iron oxide) can be electrostatically charged and also magnetized.
In a piece of iron usually the surface starts rusting leaving the interior untouched.
Is it possible to have such ...
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Simple Analogies for the Oberth Effect
I am just trying to create a simple analogy so that the Oberth effect makes sense.
Here is my best attempt:
The energy imparted by a photon to a mirror during reflection is very small. If put a ...
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Is it possible to make invisibility cloak in real? [closed]
I am a materials science undergraduate student. I have a question out of curiosity if it is possible to make a material that can completely make things invisible? What are the problems we will ...
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Control of reflected wave through metasurface
When a wave impinges on a metasurface, one can tune the metasurface to control the direction of the reflected wave. I would like to know whether it is possible to make a 3D control of the direction. I ...
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Why dispesion relation in a 2d plane related to the poles of green's function?
I'm looking at a paper about deriving the dispersion relation in a metasurface, the paper claims that
'The modes supported by an anisotropic metasurface are provided by the poles of the Green’s
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Can metamaterial works for ultra short pulses?
I have read little bit about metamaterials and understand that one can create new structure such that some of characteristic of usual elctromagnetic behaviour can be altered while propagating through ...
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Poynting vector in metamaterials
Poynting vector in a material with magnetic permeability $\mu$ is defined as
$\mathbf{S}=\frac{1}{\mu}(\mathbf{E} \times \mathbf{B})$
In certain media $\mu$ can be negative. In that case, $S$ will ...
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How derive a spring constant of a helically turned helix based on elasticity of the material and the geometry? [closed]
The structure has helicities on two levels and looks like the tungsten wire in an incandescent light bulb:
How, if at all, can the spring constant be derived from elastic properties of the material, ...
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Experimentally measure penetration depth for metamaterials?
I have simulated a high penentration metasurface design and want to fabricate it. |E|^2 decays above the metasurface with very long ~ 1um decay length.
What would be a good experimental way to measure ...
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AC field propulsion
Assuming that we have a metamaterial that can slow down the velocity of propagation of changes in an EM field to around 15 000 m/s (without felling or applying any forces), can we build a propulsion ...
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Metamaterial with index of refraction different in opposite directions
Has anyone created a mathematical model for a material whose index of refraction is different going right than it is for light traveling to the left?
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What is the difference between ordinary-spacial cloaking and spacetime cloaking?
I am unsure of what are the differences between space time cloaking and spacial cloaking, as any event can be hidden from a viewer using spatial cloaking for however long the cloaking is activated, ...
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Strange material, Bydrogen
Let's take a hypothetical scenario in which you manage to make a meta material in which the bulk of the mass is made of by a central negative nucleus and that has a single spin 1 boson whizzing around ...
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List of complex refractive indices for various frequencies and various materials
I want a list of refractive index values for various materials (or even a single material) for various frequencies / wavelengths (I need this specifically for the micro wave - radio wave regions of ...
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FDTD simulations for metamaterials and complex refractive index
I have designed a working FDTD code to simulate electromagnetic wave propagation using Yee's algorithm. I have been able to place materials such as glass slabs, etc which have positive and real ...
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What is a Material Called that Translates the Image of a Touching Object's Surface?
What is the name of a material that moves light through it in such a way that it appears that the surface of an object has translated through the material? Also, what is an example of this type of ...
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Metamaterial/Optics Book Recommendation
I recently won a prize at my school for physics (£25) for which they ask that we spend some money they have given us on a book with which they can present us during an assembly. Given that over the ...
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Would a metamaterial change its properties if one used different isotopes of an atom in its construction?
Given one had a metamaterial of a given type, containing some limited types of elements... if one were to use just one isotope of a given element (assuming it had more than one) in the construction ...
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Induced EMF in metamaterial
I am reading JB Pendry's original paper on metamaterials (Magnetism from Conductors,
and Enhanced Non-Linear Phenomena) and I am really having some trouble understanding just a few of his mathematical ...
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Perfect reflection with metamaterials with indices of refraction less than one
Total internal reflection is used to send light signals long distances in fiber-optic cables. If the cable is shaped into a ring, the light will run in a circle until its intensity dwindles due to ...