I think I have make it clear now.
Q1: I think ##TE_{20}## mode can't be generated by putting a line source in the middle of wavguide, because the distribution of electric field for the ##TE_{20}## mode at a/2 is zero, in order to generate ##TE_{20}## mode, we can put the line source in the...
In Feynman's lectures, he explained the ##TE_{10}## mode of waveguide by considering a line source in the middle of waveguide as below:
since the adjacent sources are all out-of-phase, which means to have interference, the adjacent optical path would be about half of wavelength as below:
where...
Well, I have found that the error appears in step 2.
It should be phi' instead of phi.
after that, it should be rho*cos(phi'-phi) above exp.
and then the integral would be J0.
Thanks anyway!
Homework Statement
In section 7.15 of this book: Milonni, P. W. and J. H. Eberly (2010). Laser Physics.
there is an equation (7.15.9) which is an integral representation of the zero-order Bessel function:
J_0(\alpha\rho)=\frac{1}{2\pi}\int^{2\pi}_{0}e^{i[\alpha(xcos{\phi}+ysin{\phi})]}d\phi...
there is an anthropic principle which tells that, if there is no physics, then you and your question will not be exist, so causality between these two should be clarified.
Recently I was reading some paper on design surface plasmon polaritons(so called "SPPs") on corrugated surfaces, mainly these two papers listed below:
1.Pendry, J. B., et al. (2004). "Mimicking surface plasmons with structured surfaces." Science 305(5685): 847-848.
2.Garcia-Vidal, F. J...
In Semiconductor physics and devices: basic principles
[By Donald A. Neamen], chapter 4, section 4.4, it says:
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One postulate used in the derivation of the Fermi-Dirac probability function was the Pauli exclusion principle...
I got a question when I was reading a paper, it describe a periodic structure composed of many infinite metal wire, and then try to calculate the momentum per unit length of the wire like these when there is current through wire:
electrons in a magnetic field have an additional...
I know that h_1=\sqrt{(\frac{\partial x_1}{u_1})^2+(\frac{\partial x_2}{u_1})^2+(\frac{\partial x_3}{u_1})^2}
is just the formula(6) in http://mathworld.wolfram.com/CurvilinearCoordinates.html now.
and by using the limit definitions of the divergence, I can deduce the formula like below...
[SOLVED] How to deduce rot and div formulas under spherical or cylinderical coordinat
It is said that in general, these formulas are:
if
dl_1=h_1du_1, dl_2=h_2du_2, dl_3=h_3du_3
then
\nabla \Psi=\frac{1}{h_1}\frac{\partial\Psi}{\partial u_1}\vec{e}_1 +...
IC, thanks anyway!
1.Just add several spaces as [ tex ]...[ /tex ] .
2.add two [ tex ]...[ /tex ] can print as an "enter",maybe like below:
\nabla(\bf{x}\cdot\bf{a})=\bf{a}+\bf{x}(\nabla\cdot\bf{a})+i(\bf{L}\times\bf{a})
where
\bf{L}={\frac{1}{i}}(\bf{x}\times\nabla)
thanks, I just found it^_^. and before this, I found formula I type can be shown normally, it's glad to see this. but still there are two question:
1. it says that we use tex & /tex, but how to add [] in the beginning and the end to tell others or just show this as explanation , because they...