Re: harmonics, anharmonic ...

[Ludwik Kowalski <KowalskiL@MAIL.MONTCLAIR.EDU>]

"JACK L. URETSKY wrote:

> Hi Ludwik:
> We don't have to work at the atomic level, to exhibit the
> principle of non-linear response functions for intense
> radiation. Just realize that at high intensities the transmitted
> (and, hence, reflected) waves in a medium are proportional
> not just to E, the electric intensity, but also to E^2, etc.
> But if E carries a single frequency, then E^2 carries the
> doubled frequency, etc.

What do you mean by "waves are proportional"?

Sure, if y1=f(t) is a sine curve then y2(t)=y1*y1 (which is
never negative) has the frequency which is twice as large as
that of y1. In this thread y1 happens to represent E.

We have only one frequency at the input and two at the
output. I do not see how this can be explained without
addressing the interactions at the submicroscopic level.
To ignore atoms we must have a nonlinear relation
between two macroscopic parameters, like in a diode.
What versus what is macroscopically nonlinear to
explain the appearance of green light?

Ludwik Kowalski