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fredrick08
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Homework Statement
A 10eV electron is incident on a potential barrier of height 25eV and width 1nm. Estimate (order of magnitude) the probability that the electron will tunnel through the barrier, repeat your calculations for a barrier of 01.nm
Homework Equations
T=16(E/V)(1-(E/V))exp(-2[tex]\alpha[/tex]a)
[tex]\alpha[/tex]=[tex]\sqrt{}(2m(V-E))[/tex]/[tex]\hbar[/tex]
The Attempt at a Solution
E=10eV=1.6x10^-18J, V=25eV=4x10^-18J
[tex]\alpha[/tex]=[tex]\sqrt{}(2*9.1x10^-31(4x10^-18-1.6x10^-18))[/tex]/6.62x10^-34=3.157x10^9
T=3.84exp(-2*3.157x10^9*1x10^-9)=7x10^-3?
the answer is meant to be 9.2x10^-9 or 4.95x10^-13? sorry, my book says 4.95 and the lecturers notes say 9.2... doesn't matter, coz I am way way off...
please can someone help me where i am going wrong?