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# Quantum Mechanics - Tunneling watch

1. An electron confined by a potential barrier may surmount it by thermal excitation instead of tunnelling through it. Which process is the more likely if the barrier is 0.5 eV high and 2 nm thick and the ambient temperature is 300 K?

Dont really know how to do this one
2. You'll have an approximate expression in your notes for the tunnelling amplitude

And thermally means that you'll need to use a boltzmann-type expression

so compare them, you might need to think about normalisation but i'll let you think about that (or answer it when i get back)
3. (Original post by MC REN)
You'll have an approximate expression in your notes for the tunnelling amplitude

And thermally means that you'll need to use a boltzmann-type expression

so compare them, you might need to think about normalisation but i'll let you think about that (or answer it when i get back)

I have no clue what kind of Boltzmann expression I'm meant to be using lol...The only resemblance is they both contain exp(-stuff)...not sure how this would help though
4. http://en.wikipedia.org/wiki/Boltzmann_factor

And it needs to have enough energy, Ei, to escape over the barrier, which is going to be the charge times the voltage height of the barrier

when you have expressions you basically have the probability of it occuring like that so whichever one is largest is the most likely
5. dang it, seems so obvious now, ty

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