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Yes, this is precisely how several elements that aren't found on earth were synthesized. Look up the history of elements like Berklium and Californium, for example.


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What you can do is find out the illuminance (lux=lm/m2) of a magnitude 6 star, which is the limit of human vision of light spots and see what luminous flux (lm) creates that illuminance at your certain distance from the spot, assuming that the light disperses uniformly in a semisphere (unless you have better information on the light distribution). From the ...


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A 1 mW red (diode) laser will make a dot visible many meters away, is cheap, widely, legally available, not dangerous and uses little electricity.


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Even if the laser had perfectly reflecting, i.e. lossless, mirrors at either end of the cavity, and both ends were sealed so no light could escape it would still require a continual power input. That's because excited atoms/molecules can decay by mechanisms that don't involve a photon e.g. collisional de-excitation. The lost energy goes into heating up the ...


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Polarization maintaining fibers are (as far as I know always) single-mode fibers. It is inherently difficult to efficiently couple light into single-mode fibers because, by definition, they will only support one specific optical mode which you have to carefully match with your input beam. So this mode matching will most likely be your main challenge. Getting ...


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A laser is just a thin slice from the spectrum of light. Is it more efficient compared to the visible spectrum of light? It depends on the frequency of the laser and how efficiently the solar panel can turn light of that frequency into electrical energy. If a solar panel would operate better/best with light of a certain frequency, using a laser with that ...


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In my experience (PhD student working on laser plasma interaction experiments) these PIC codes are pretty closely guarded by their creators. There are a few out there, for example OSIRIS, VORPAL, and TurboWave in addition to VLPL. Of these I think only VORPAL is commercially available (through Tech-X) and the others you would need to contact the groups ...


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Theoretically yes, the laser principle does not consume any material. There is a light source that excites the electrons in the material to higher levels, they deexcite to some intermediate one, here the avalanche of photons appears producing the laser light and leaving the electrons in the ground state. And you can repeat the process without a loss.


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theoretically if its components never wore out then yes. however in practice things do wear out eventually and so no it could not be done in the same way that a perpetual motion machine can work in theory but not in practice.


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Technically, the coherence time will remain the same. This will be determined by the width of each frequency component in the pulse, which does not depend on the phase relationship. Another way of thinking about it is that coherence time = coherence length / phase velocity. Consider free space, where group velocity = phase velocity. The coherence length is ...


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A year later, here is a probabilistic (pseudo QM) explanation. I am confused by the diagram that appears to show unpolarized laser light - I thought that most lasers by their nature produce polarized light; after the first polarizer that question is moot, so let's start there. A polarized photon can be thought of as being in a mixture of states - when it ...


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It's true that laser's traditional applications are related to their monochromatic (one wavelength), collimated (one direction) and coherence ("one phase" or phase matching) characteristics. Laser beams have low dispersion, can be amplified and focused to reach very high photon densities and pulse shape can be sculpted at will. Many applications are only ...


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Pieced together from other discussions: The only way to get large amounts of monochromatic and/or collimated light is through stimulated emission, which happens to also produce coherent light. For example, if we want a more collimated LED then we we end up with a diode laser. And if we want to more collimate the output of an arc lamp we have to introduce ...


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Given that most green pointers are frequency doubled from a 281.8 THz infrared laser ($c$/1064 nm), it's possible that you have a two frequencies $f_1$ and $f_2$ in the original infrared laser (i.e., it is multimode). After passing through the "frequency doubling" nonlinear crystal you see three frequencies: $2 f_1$, $2f_2$, and $f_1 + f_2$. It looks like ...


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When you first apply current to a laser diode, it does behave as an LED. Light is output across a (relatively) broad spectrum by spontaneous emission. But once the current reaches the threshold current, then positive feedback causes one (or a few) modes to oscillate. Further increases in input power will increase the ouput in those particular modes, but the ...


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They already exist. "Solar-pumped lasers already exist: they work by concentrating sunlight onto crystalline materials such as neodymium-doped yttrium aluminium garnet, causing them to emit laser light." (source) They have been innovated though, so there are more efficient method to make solar-powered lasers now.


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Any thoughts on the second question? Could laser damage the dna, or perhaps bones, which could result in some cell damage-cancer? How deep laser go? What I need to know about it?


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An aspect I learned, which is different from the other answers given here, centers around the fact that an energized lasing medium will react to photons which go through it by producing more photons along the same path, but will also spontaneously release photons traveling on random paths. Any energy the lasing medium spends doing either of those things ...



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