4
votes
Accepted
Are GHZ states absolutely maximally entangled?
I think the issue here is the definition of Absolutely Maximally Entangled (AME) states on Wikipedia, which you are quoting. I had not heard of AME states before, but after coming across your question,...
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votes
GHZ Definition - Does it all have to be $|000\ldots\rangle$ or $|111\ldots\rangle$ or can it be $|010\ldots\rangle$ or $|101\ldots\rangle$
TL;DR: No, these are not GHZ states. They are cat states.
GHZ state
The GHZ state is defined as the state
\begin{equation}
\frac{|000\rangle+|111\rangle}{\sqrt{2}}.\tag1
\end{equation}
Generalized GHZ ...
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3
votes
Accepted
Output of my quantum circuit to create 3-qubit GHZ-like state does not make sense mathematically
As @Callum said, your ordering of qubit is wrong. Qiskit keeps the 0th qubit at the rightmost space in a ket representation or for measurement.
If you have, say 3 qubits, qubit#1, qubit#2, qubit#3, in ...
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votes
Accepted
2
votes
Why does measuring a GHZ state in the computational basis destroy the entanglement?
The two-qubit GHZ state (Bell state) case is special: any measurement in a basis
$$
\cos\theta X+\sin\theta Z
$$
will return perfectly correlated results between the two parties.
In the case of a ...
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2
votes
What is the general form for GHZ and W class states?
The GHZ form of the state follows from a bit of a manipulation after define what you mean by a GHZ state, remembering that all these parametrisations are "up to local unitaries". For me, the ...
- 60.7k
1
vote
Are GHZ states absolutely maximally entangled?
For higher order GHZ states, like as you said for four qubits case, we can write the density matrix of this state like the following:
$$\rho_{ABCD} = \frac{1}{2}(|0000⟩⟨0000|+|0000⟩⟨1111|+|1111⟩⟨0000|+...
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vote
Are GHZ states absolutely maximally entangled?
I suppose the term "Reduced Density Matrix" makes sense here. As we have a three qubits system GHZ state such the following:
$$|\psi⟩ = \frac{1}{\sqrt{2}} (|000⟩ + |111⟩)$$
If we build the ...
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vote
Transferring GHZ state onto some qubits
About checking.
I do not quite understand why you can't check how the GHZ-state was teleported in the most ordinary ways: in addition to measuring the state immediately after teleportation, as well as ...
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