For the entanglement qubits, when we measure one qubits, the other qubits will collapse to a quantum state. How can I get the amplitude of other qubits. An example is as follows:
The init quantum state: \frac{1}{2}|0>|0> + \frac{1}{2}|0>|1> + \frac{1}{\sqrt{2}}|1>|0> + 0|1>|1>
\Rightarrow \frac{1}{2}|0>(\frac{1}{\sqrt{2}}|0> + \frac{1}{\sqrt{2}}|1>) + \frac{1}{\sqrt{2}}|1>(1|0> + 0|1>)
So it means that for the first qubit, we have \frac{1}{2} probability of measuring 1 and \frac{1}{2} probability of measuring 0.
When we measure the first qubit, if the result of qubit 1 is 0, then the second qubit will collapse to \frac{1}{\sqrt{2}}|0> + \frac{1}{\sqrt{2}}|1>. And if the result of qubit 1 is 1, then the second qubit will collapse to 1|0> + 0|1>.
This is a very interesting phenomenon, but how do we implement it in pennylane. When I use mid-measure, the output of other qubit has no influence. Any help will be appreciated.