Actually, if you want to get technical, no laser is truly monochromatic. Some are closer than others and can be treated as such to a very good approximation, but the laser would have to be emitting light for all eternity to be considered purely mononchromatic.
Another factor in creating a...
Wow, I wish I had seen this thread earlier. The whole point of my PhD thesis was finding a simple material that you could get slow light (group indices ~10^6). One of the simplest is ruby. http://www.optics.rochester.edu/workgroups/boyd/slowlight/slowlight.html a link to the group where I...
I think that the answer to your question is no (although someone may correct me). The magnetic field (in the Faraday effect) breaks the symmetry of the situation. Suppose you send linearly polarized light (say s-polarized) through a Faraday rotator that rotates the light 45 degrees. If you...
I'm not sure if the physics is analogous. Photons are bosons so they can occupy the same state. As long as the phase of both beams are carefully controlled, I don't believe that there is anything that prevents the merging of two beams at a beam splitter.
Beam tubes also serve the purpose...
Another way of saying this is the most important aspect of a pulsed laser is that they can produce high peak powers. There are two "powers" associated with pulsed lasers: the peak power and the average power. For a CW laser (non-pulsed) these are the same. The average power is the amount of...
Cold lasers? The prof may have been talking about laser cooling (see Lurch's link). You can use lasers to slow down the velocity (and thereby lower the temperature) of atoms. You cannot slow down electrons in their orbitals. Now maybe the prof didn't want their laser to get too warm (like...
chroot, I think you are being a little harsh. Yes, QT's essay is far from perfect, but his understanding of lasers is far better than I had at that age. Also, I'm not concerned at all about any misspellings in QT's post.
QT, if you’re interested, here are a few more corrections that jumped...
Well, it's not like you can study an E-M wave under a microscope. An alternating electric and magnetic field may be the best you can do.
http://www.colorado.edu/physics/2000/waves_particles/
Thinking about it, I think you may be right. The light I saw may have been florescence. It was a pulsed excimer laser with ~200 mJ per pulse, average power of a couple of Watts. For the most part, I was careful to keep my laser goggles on, but once or twice I had them off and you could see a...
I've worked with lasers on both ends of the spectrum, and believe me, if it's bright enough you can see it. I'm color blind so I can't see that far into the red, yet even I have seen above 800 nm. I've also seen light @ 351 nm. Your eye sensitivity drops off slowly; there is no sharp cut-off...
You are in good company then. Photons are confusing. Asking what the size and shape of a photon is somewhat meaningless since it is a quantum mechanical "entity". You can describe a wave function which can be more or less localized, but it is a mistake to try to think of it as classical...
The phase velocity can be thought of as the speed of a pure monochromatic wave or the speed of a single frequency. Specifically, it is the speed of the peaks and troughs that make up the wave.
The group velocity can be thought of as the speed of the propagating temporal interference pattern...