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Matlab Plotting of QM double-potential-barrier

  1. Apr 29, 2009 #1
    Hey everyone, I have a quantum mechanics/matlab issue. I'm trying to plot the Transmission Coefficient T(E) of a double-potential barrier with barrier width 3nm and spacing 9nm, potential V = 0.5eV and sweeping energy from 0 to 1eV. Using the cascading matrix method where, given a matrix M of each interface, the beginning and end coefficients of the wavefunctions can be found, with the end wavefunction having a coefficient t and |t|^2 gives the transmission. One would have to probably be familiar with this QM problem to get the whole idea.

    Anyway, I wrote out a function to do just what was described, and came across an oddity. I get the correct graph, except it's flipped upside down and rather than being between 0 and 1, it's between infinity and 1, but on the correct scale. see the image below; can anyone pick through this code and possibly see where i've gone wrong or why this graph is showing up the way it is? if someone had some free time i'd really appreciate it, i've been hitting my head against the wall for 2 days now. thanks!

    attached image
    top: desired plot
    bottom: my plot (notice the y axis)


    Attached Files:

  2. jcsd
  3. May 6, 2010 #2
    maybe you can help me with a program?
    im trying to plot the transmittion coeffiecet vs energy
    for an arbitrary seriers of step potencials with the same step potencial and length
  4. Oct 22, 2011 #3
    please i have another problem i want to get the graph of energy vs barrier width .i hav done the program in wolferm methamatica but cannot find the output .plz help
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