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What i mean is for example exclusively red light comes in but gets reflected or refracted as blue or xray wavelength or whatever. Does this happen at all?

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    $\begingroup$ I am not aware of any material that alters the wavelength of a photon during the duration of its existence; however, there are materials that absorb photons of certain wavelengths and then emit photons of new wavelengths: en.wikipedia.org/wiki/Phosphorescence and en.wikipedia.org/wiki/Fluorescence $\endgroup$
    – Nick
    Jan 25, 2014 at 23:14
  • $\begingroup$ Also check out en.wikipedia.org/wiki/Nonlinear_optics $\endgroup$ Jan 25, 2014 at 23:18
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    $\begingroup$ In general, yes. Any material with a nonlinear response to electromagnetic radiation is susceptible to perform wavemixing at sufficiently high light intensities, and even the vacuum becomes nonlinear at exorbitantly high intensity. $\endgroup$ Jan 25, 2014 at 23:18
  • $\begingroup$ @DumpsterDoofus: You say "Vacuum becomes nonlinear at exorbitantly high intensity". Do you mean according to some theory, or in reality? $\endgroup$ Jan 26, 2014 at 1:11
  • $\begingroup$ @JánLalinský: AFAIK, only in theory (en.wikipedia.org/wiki/Schwinger_limit), although supposedly inelastic nonlinear scattering in vacuum has been experimentally observed. The case of mixing in matter is of course well-known. $\endgroup$ Jan 26, 2014 at 1:17

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Going from low energy to high energy is remarkably commonplace. Anyone who carries a green LASER pointer may not realize it, but the origin of the electromagnetic radiation can be (and commonly is) an infrared AlGaAs laser diode operating at 808 nm, which is then pumped through a material such as Nd:YVO4 which increases the wavelength to 1064 nm it is then pumped through potassium titanyl phosphate which decreases the wavelength to 532 nm - effectively a frequency doubler.

There are filters and exact crystal alignment to take into account of in the manufacture of these items, but they are commonplace. (See here)

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Going the other direction--from high energy to low energy--is fairly common in materials called wavelength shifters. https://en.wikipedia.org/wiki/Wavelength_shifter

Compton scattering also can change the wavelength of light form high energy to low energy.

Strong gravitational fields will also change the wavelength of light. So the sunlight we see is very slightly more red than the light that is emitted from its surface. https://en.wikipedia.org/wiki/Gravitational_redshift

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Almost all incoming light radiation including infrared interact with soil on the earth's surface, either getting absorbed or reflected back or getting transmitted or scattered. Even the soil formation begins with light on the wet condition of rock materials. Photopedogenesis, however, explains qualitatively about light penetration in soil in presence of moisture. But, physical behaviour of light within soil is still a strange and needs quantitative explanation.

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Yes there are. Precious stones normally do that.

For example, consider ruby which is a single cristal of $Al_2O_3$ with impurity of $Cr^{3+}$. It has energy bands as follows,

enter image description here

The incident visible light has not enough energy to excite electrons from the valence band (dark band) to the conduction band (empty withe band) since the most energetic wavelength (violet) is only around $3.1\, eV$. On the other hand, electrons can be excited to the two intermediate bands and two intermediate lines that appear due to the doping. Once they are excited (at most to the band centered at $3.1\, eV$) they start to decay, such process that must respect some selection rules. Some of the radiation emitted in on the infra red regime, but the line at $1.78\, eV$ allows for electron decaying to the valence band and emitting photons in the red wavelength. Therefore ruby is transforming a whole spectrum of visible light into red light.

By the way, the single cristal of $Al_2O_3$ is a sapphire, which is transparent. When doped with chromium it becomes the ruby. If you dope with iron and titanium it becomes the blue sapphire and so on.

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