Hello, first post on these forums... I read up on the rules and such but please excuse me if i missed something.(adsbygoogle = window.adsbygoogle || []).push({});

I am making a simulation of a bessel beam (non-diffracting and self healing) in MatLab but I do not know how to define the wave vector. More specifically, the transverse (k_{T}) and the propagation constant (k_{z}). If i can find one of them, I can solve for the other.

The "governing" equation I am using is:

U(r)=J_{0}(k_{T}*rho)*exp(-j*k_{z}*z)

J_{0}is the zero order Bessel function of the first kind, rho is just sqrt(x^2+y^2), j is imaginary number, z is distance along the z-axis.

The relationship between the wave vectors is:

k_{T}^{2}+k_{z}^{2}=k^{2}

Now, a fellow labmate initially had told me that for a gaussian beam, you usually set z=0 and solve for k_{z}because at the z=0 plane, all the wave vectors point only in the z-direction and thus k_{T}=0. However this will not work because if z=0 and k_{T}=0 then the equation above yields a plane wave.

This is just a summary of my problem . If you need more information, I will be happy to provide it.

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# (Bessel Beam) Wave vector question

Can you offer guidance or do you also need help?

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