Do Lasers Have Harmonics Like Sound Frequencies?

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Lasers can exhibit harmonic frequencies similar to sound, but they typically operate at a single fundamental frequency. For example, a laser emitting light at 500 nm can theoretically have a third harmonic that corresponds to three times its frequency. However, most lasers are designed to emit primarily at their fundamental frequency, with exceptions like green laser pointers, which operate at the second harmonic of a near-infrared frequency. The conditions necessary to produce standing waves with light are not practically achievable. Understanding these principles helps clarify the behavior of laser frequencies.
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Homework Statement


Hi all.

When talking about sound, we tak about the fundamental frequency, the first harmonic, second, third etc.

Does this also work for lasers, i.e. for light? So if I have a laser at 500 nm, then the third harmonic is 3 times the frequency that corresponds to 500 nm?


Niles.
 
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Good question, and I'm not totally sure.

The one thing I would say is that the conditions in order to produce a standing wave would never ever happen with light, perhaps theoretically if you could somehow have a fixed beam of light and control it with a perfect mirror, I'm not sure but i'll go with ; practically - no! =P
 
Niles said:

Homework Statement


Hi all.

When talking about sound, we tak about the fundamental frequency, the first harmonic, second, third etc.

Does this also work for lasers, i.e. for light? So if I have a laser at 500 nm, then the third harmonic is 3 times the frequency that corresponds to 500 nm?


Niles.

Yes, that is true. Note however that most lasers operate at just one frequency, the fundamental, to a very good approximation. An exception to this is a typical green laser pointer; the green light is the 2nd harmonic of the fundamental, near-infrared frequency.
 
Thanks for that.
 
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