We have a particle of energy E crossing a potential jump at x=0. for x<=0, V=0, for x>=0 V=V1(adsbygoogle = window.adsbygoogle || []).push({});

We get a wavefunction for x>=0 psi(x) = exp(-iEt/hbar)*exp(-Kx)

where K = (2m(V1-E))^0.5/hbar

N.b E<V1 so classically we get no transmission

we are asked to estimate the penetration distance, and I have found a solution which says let the penetration distance equal 1/K. I can't see physically why we would pick this (it just seems like a random number that means that the wavefunction will decrease by a factor 1/e, but I can't see why this is a sensible estimate).

Thanks

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# Homework Help: QM - barrier penetration

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