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comment about to create a standing wave
For example, the optical lattice stated in en.wikipedia.org/wiki/Optical_lattice, is using two counterprogating laser beam to form the standing wave. Since $\cos(\omega t)$ will be there as a result of the amplitude-modulated standing wave, so I think $\omega$ is the resonance frequency between any two atomic levels which the laser beam operating to, isn't it? Usually, will $\omega$ be so high? And if so, the amplitude of the standing wave is modulated in such high frequency, can we consider it (amplitude) as a constant instead of modulation?
Jan
4
comment about to create a standing wave
Thanks a lot. It is clear now. But another question just comes up to me. If people use the laser to create the optical standing wave, so the term $\cos\omega t$ that modulate the amplitude is related to the frequency of the laser? Since the frequency is so high, what do we see for optical standing wave then?
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accepted about to create a standing wave
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comment about to create a standing wave
Thanks Brionius. That helps to clarify my question. So the amplitude of the "standing wave" is not constant as stated in the text, is it only stationary in space but the amplitude is still changing in time, right? For 3, I should not use the word 'propagate', I mean there are two standing waves along two direction making 30 degree. I wonder how to visualize that 2D standing wave then?
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accepted about superposition of two sinusoidal waves
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9
comment about superposition of two sinusoidal waves
Oh, I see, that's how we average them in time. Thanks a lot
Oct
9
comment about superposition of two sinusoidal waves
Thanks Rob. I see your point now. Yes, it doesn't make sense to have different unit on both side since the intensity should be defined as the amplitude square (without time). But then how to get $I = I_1 + I_2 + 2\sqrt{I_1I_2}\cos(\phi_1-\phi_2)$ in the wiki en.wikipedia.org/wiki/Interference_%28wave_propagation%29 ?
Oct
9
comment about superposition of two sinusoidal waves
Thanks for the reply. If I integrate from 0 to a unit time, i.e. 0 to 1, the sin term will remain in the result !?