Curious question about light/photons

[JG Questions]

MichaelCC,
Like shining a red light through blue jello? no light comes out.

Do you mean that you can use glass as a delay for light so a single beam that is split so one the goes through air can be phase shifted from the one that went through glass?
Jon B

married back together after processing to intensify one frequency

 

[mfb]

Apart from a few special conditions, you also cannot just merge two sources of light to get a higher intensity without problems. You lose some other property, e. g. you have a larger angular spread of your light afterwards. If you just care about intensity, yes, you can increase the UV intensity a bit. Where is the point?

 

[JG Questions]

Apart from a few special conditions, you also cannot just merge two sources of light to get a higher intensity without problems. You lose some other property, e. g. you have a larger angular spread of your light afterwards. If you just care about intensity, yes, you can increase the UV intensity a bit. Where is the point?

What % of light does a photovoltaic transfer into energy? 20%?

 

[mfb]

Depends on the cell and the incoming light. 20% are realistic for commercial large-scale cells with sunlight. Nearly 50% have been demonstrated in the lab, and for monochromatic light even more is possible (e. g. https://www.researchgate.net/publication/224445543_III-V_solar_cells_under_monochromatic_illumination ).
All those numbers are easy to look up.

I still don't see where this would lead to.

 

[JG Questions]

theoretically you could change the wavelength of light that isn't picked up by photovoltaic into range, and then to ensure that even on low contact periods energy is still collected, you could change longer wavelength light into ultraviolet light and raise the efficiency of the energy collected. Or, create a new way of collecting energy from wavelengths closer to x-ray/ spectrum and shift the frequencies to higher energy wavelengths to create wavelengths that we get little of here on earth

 

[mfb]

Yes, and that idea is discussed in hundreds of papers, see also post #18.
Various google results.
So far, it is more efficient to add layers that are sensitive to longer wavelengths, instead of lossy conversion processes.

 

[Neandethal00]

If a photon wavelength (yellow) is isolated from the other wavelengths that sunlight emits (once it gets to earth), can that particular particle/photon be distorted slightly into a wavelength that is shorter (perceived as green)?

Collisions (scattering) with around 25000 electrons, which is not too high compared to the path the photon will travel, will increase its wavelength from 510 nm to 570nm by Compton Scattering.

 

[JG Questions]

Yes, and that idea is discussed in hundreds of papers, see also post #18.
Various google results.
So far, it is more efficient to add layers that are sensitive to longer wavelengths, instead of lossy conversion processes.

Thank you, i think you helped me immensely

 

[JG Questions]

so, It's taken 19 posts for you to get to the core of what this thread is all about

you said "we" ... are you stating that you are part of this engineering team ?

and what does this new info have to do with your original Q ?Dave

I had a couple talks with some leaders in the advancement in quantum computing yes. I am just being curious, and my original question is incredibly related i believe.

 

[JG Questions]

Why do you want to change the frequency? Changing intensity or polarization is so much easier. And even that is a very challenging task. Optical computing has some interesting applications, mainly for fast internet data transfer (where the data transmission is optical already, so you save two conversion steps). I don't think replacing a whole ALU or even the whole CPU with optical elements is a realistic option in the near-term future.You cannot reduce entropy, and you cannot violate conservation of energy either. Upconversion of infrared light for photovoltaics is studied, but multiple layers sensitive to different wavelength ranges are possible as well.

Quantum computing needs exactly that, replacing the ALU with optical elements

 

[mfb]

Quantum computing needs exactly that, replacing the ALU with optical elements

Depends on the objects used for computation.
And for quantum computers, you do not replace the ALU. You add a quantum system to a classical computer design, in the same way today's computers have specialized floating point units.

You keep mixing unrelated concepts here.

 

[Redbelly98]

Collisions (scattering) with around 25000 electrons, which is not too high compared to the path the photon will travel, will increase its wavelength from 510 nm to 570nm by Compton Scattering.

Compton scattering was my first thought as well. But I don't follow why 25,000 would be necessary, it should be possible with one collision if the electron has the right amount of KE.

http://phys.org/news/2015-05-team-big-faster.html

Am I the only one who wonders about news titles that read "Computing at the speed of light" when talking about optical computing? To my knowledge, conventional electronic signals propagate at speeds comparable to c as well. At least that's true for signals traveling down coax lines, I'm not certain about propagation inside a chip.

 

[mfb]

Compton scattering was my first thought as well. But I don't follow why 25,000 would be necessary, it should be possible with one collision if the electron has the right amount of KE.

I guess that number was assuming electrons in solids - nearly at rest.

Am I the only one who wonders about news titles that read "Computing at the speed of light" when talking about optical computing?

It makes great news titles. Light in vacuum is indeed a bit faster than electric signals in cables, but that advantage gets lost with glass fibres.