In: Physics
2. (a) Write down the Time Dependent Schr
this all comes under topic Finite potential well.
a)
where
,
is Planck's constant,
is the mass of the particle,
is the (complex valued) wavefunction that we want to find,
is a function describing the potential energy at each point
x, and
is the energy, a real number, sometimes called eigenenergy.
wavefunction is defined such that:
Inside the box
Outside the box
We see that as goes to
, the
term goes to infinity. Likewise, as
goes to
, the
term goes to infinity. As the wave function
must have finite total integral, this means we must set
, and we have:
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and | ![]() |
Next, we know that the overall function must be continuous and
differentiable. In other words the values of the functions and
their derivatives must match up at the dividing points:
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|
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These equations have two sorts of solutions, symmetric, for
which and
, and antisymmetric, for which
and
. For the symmetric case we get
so taking the ratio gives
note L= 130 pm
b)
where
and m = mass of particle
c)