Quantum Optics wave amplitude question

[Master J]

In quantum optics, I've been looking at how one can show electromagnetic field is equivalent to a harmonic oscillator.

They give the E field as, in one dimension:

E_x (x,t) = A . cos(wt) . sin(kz) where the symbols have their usual meanings.

A is given as SQRT[2w^2 / Ve]

here, w is omega, V volume of cavity, e is permittivity of free space. I cannot find an answer however to where this amplitude A comes from. In two quantum optics books I have looked at, they simply introduce it without explanation.

Any help??

 

[azntoon]

The amplitude A comes from the fact that the electric field is a harmonic oscillator. The electric field is a sinusoidal wave, and this sinusoidal wave is related to a harmonic oscillator. In order to properly describe a harmonic oscillator, we must have an amplitude A associated with it. This amplitude A can be calculated using the equation above, which uses the parameters of the harmonic oscillator (w, V, and e) to calculate the amplitude of the electric field.