In deriving the results for the eigenstates of the annihilation operator
I discovered my derivation had an overall factor of
was missing. I traced
this to a bad definition in my previous notation and a misunderstanding on my
part (carelessness). To correct the
notation I will introduce the following:
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states that are built using the creation operator |
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states generated by the annihilation operator |
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Normalized statesè |
These states are all proportional to each other.
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For convenience we define states that are simply related by
the raising and lowering operators with no additional constants
and
. Starting with these
simple properties we can find the the way these states behave with both
operators,
, and find a normalized state its properties under the
operations.
When introducing these operators the book simply states “apart from normalization factors”. Using these operators one can show that the creation operator produces a state that is next higher energy and the annihilation operator produces the next lower energy state. The operator
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the number operator, has these states as eigenvectors and the eigenvalue is n.
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Remember that if
then
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The characteristics of the state don’t depend on these multiplicative factors but of course we prefer to use normalized states so that one can write down probabilities and probability densities.
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In my original development I assumed incorrectly that
notice
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so the state |
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Find the factors that relates the states.

Remember that the definition of the states
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Similarly



Same as above. Thus an acceptable value for the coefficients
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We have already seen that a definition of the normalized states is

The inpact of
on these states is

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With the correct definitions for the states and the correct
results for the
and
on the states, we can
find the eigenvectors for
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