Question about electromagnetic metamaterials

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The discussion centers on the behavior of light when interacting with alternating sections of metamaterials and conventional materials with equal and opposite refractive indices. It highlights that while metamaterials can manipulate light in unique ways, basic optical principles like using a lens can achieve similar effects without needing metamaterials. The conversation also touches on the potential for metamaterials to enhance solar cell efficiency by creating broadband resonant cavities that optimize light absorption across various frequencies. Additionally, it emphasizes the importance of understanding refractive index gradients for steering light direction. Overall, the exploration of metamaterials reveals significant possibilities for advanced optical applications.
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If someone made something with alternating sections of metamaterial and conventional material, that were of equal and opposite refractive index over the spectrum of interest, what would happen to the incoming light? Would it travel at right angles to the material? If the refractive index of the two materials were different in magnitude, could you steer the incident light in any direction? What configuration could allow the light to concentrate on one spot? What configuration could allow diffuse light to become light that exits on the other side of the material in the same direction without filtering the light? What configuration could allow the light to loop around in the material?
 
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The definition of metamaterial is an artificial material that is not readily available in nature. In terms of refractive indicies, this usually means materials which have specially tailored absorption profiles, and where the light used is close to the resonances in the material. This can lead to light traveling both very slow and faster than normal.

However, your subquestions does not necessarily have anything to do with metamaterials. For example, to concentrate the light to one spot all you need is a normal lens. More generally, to bend the light in any direction you just need a refractive index gradient along the direction that you want to turn it to. This could be done by changing the object shape or by letting the material consist of different subcomponents with varying index. Note that this does not make it a metamaterial, infact such materials exist in nature, for example fish eyes use this technique.

Maybe you want to read up on metamaterials on some general site (like wikipedia) and make your questions a bit more specific.
 
My question is about what possibilities exist for metamaterials, particularly if you had a composite of conventional material and metamaterial. I'd like to know how much control people could have over properties like refraction and dispersion in these metamaterials over a range of light frequencies. I'm asking out of curiosity more than anything else.

There is one application I'm wondering about though. Making a broadband resonant cavity for solar cell appilications. If there's a metamaterial that can have well defined dispersion properties then I think that it's possible to fit a range of frequencies in a resonant cavity so that, in my understanding, there are more opportunities for the solar cell to absorb light energy. Even if the metamaterial was active, if the energy input was a small fraction of the potential sunlight available, then the solar cell might be more efficient than what is currently available.
 
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