Question

An electron having total energy E = 3.40 eV approaches a rectangular energy barrier with U = 4.10 eV and L = 950 pm as shown in the figure below. Classically, the electron cannot pass through the barrier because E < U. Quantum-mechanically, however, the probability of tunneling is not zero.

(a) Calculate this probability, which is the transmission coefficient. (Use 9.11  10^-31 kg for the mass of an electron, 1.055  10^-34 J · s for ℏ, and note that there are 1.60  10^-19 J per eV.)

(b) To what value would the width L of the potential barrier have to be increased for the chance of an incident 3.40-eV electron tunneling through the barrier to be one in one million?

Answer 1

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