Hi,
I wanted to plot the lightcone by plotting kmag versus k1 and k2 in a
triangular lattice. However, it does not look like a cone(segment).
Plotting it versus sqrt(k1^2+k2^2) works of course.
Hence, I was looking at the calculation of kmag, but couldn't find it.
E.g. starting from the tri-rods.ctl file, with a small change in the
geometry lattice (reciprocal lattice vectors at 60° from each other)
(set! geometry-lattice (make lattice (size 1 1 sz)
(basis1 (/ (sqrt 3) 2) 0.5)
(basis2 (/ (sqrt 3) 2) -0.5)))
one gets that:
k1 k2 k3 kmag/2pi (comment)
0.3333 0.3333 0 0.3849 (K-point)
0.5000 0 0 0.5774 (M-point)
However, in this basis, the magnitude of the vector Gamma-K should be
1/sqrt(3), no? Likewise, the M-point is also not giving me the kmag/2pi
value that is shown.
I'm missing something obvious, I'm sure, but I can't find it. Any help?
Thanks!
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