91影视

The probability that is given by the transmission coefficient T is as follows.

$\mathit{T}\mathbf{=}{\mathit{e}}^{\mathbf{-}\mathbf{2}\mathbf{b}\mathbf{L}}$, where $\mathit{b}\mathbf{=}\sqrt{\frac{\mathbf{8}{\mathbf{蟺}}^{\mathbf{2}}\mathbf{m}\left(U-E\right)}{{\mathbf{h}}^{\mathbf{2}}}}$

Here, U is barrier of height and L is the thickness.

According to these equations, the transmission coefficient decreases as the potential height increases and also decreases as the energy of the incident beam decreases, it can be observed that, it depends on the value of $\sqrt{\mathbf{U}\mathbf{-}\mathbf{E}}$increases the transmission coefficient decrease. Also, the transmission coefficient depends on width of the barrier, so,

$\mathit{T}\mathbf{鈭�}{\mathit{e}}^{\mathbf{-}\mathbf{L}\sqrt{\mathbf{U}\mathbf{-}\mathbf{E}}}$

From the graph, it can be observed that the graph between L and T is a decreasing exponential. It is known that the curve with a greater values have the smaller factor in the exponential, since the only difference is in the barrier height, then the curve with the higher barrier height has a smaller values of T , therefore the rank of the potential step height is $U_3>U_2>U_1$.

Hence, the rank is $U_3>U_2>U_1$.