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What is quantum gate teleportation?

Quantum gate teleportation is the act of being able to apply a quantum gate on the unknown state while it is being teleported. This is one of the ways in which measurement-based computation can be ...
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Does entanglement allow enhanced communication efficiency?

First, about teleportation, you say that you think quantum communication takes place in the protocol, but it doesn't. They only share an EPR pair they created together, hence the coordination and ...
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When you act on a multi-qubit system with a 2-qubit gate, what happens to the third qubit?

Whenever you have a quantum gate (like a CNOT) acting on some qubits but not others, it is assumed that the other qubits are acted on with the identity operator. This is done using the "Left Kronecker ...

Compute the output of the quantum teleportation circuit

Since your circuit is teleportation, $|C\rangle =|\varphi\rangle$ and since you measured $|11\rangle$ on $|AB\rangle$ the answer is $|ABC\rangle = |11\rangle|\varphi\rangle$. Now, let look why this ...
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What happens to the Bell state qubits after the Quantum Teleportation?

They get measured as part of the teleportation. It doesn't matter what happens to them after that. You can throw them away, reset them back to $|0\rangle$ and re-use them for something else, whatever.
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Is it possible to have Quantum Teleportation Protocol without using classical channel?

This "protocol" is completely wrong. The author is simply preparing the state $|\psi\rangle$ on Bob's side and leaving it there untouched. Meanwhile, Alice prepares a maximally entangled ...
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how to prove quantum teleportation can't be achieved by sending only one classical bit

Alice sent 1 bit to Bob. But that bit contained 1 qubit (via too good teleportation). But that qubit contained 2 bits (via superdense coding). But those 2 bits contained 2 qubits (too good ...
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What is the maximum separation between two entangled qubits that has been achieved experimentally?

I believe the current record is held by the Jian-Wei Pan group in China, who are able to generate entanglement via a satellite. The journal article is here, while there's plenty of media coverage that ...
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Understanding this description of teleportation

The first two qubits stay on the sender's side, and since they are not entangled with the receiver's qubit, it's not necessary to mention them any further — we switched to discussing the receiver's ...
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Generalising the standard quantum teleportation protocol: what are the possible unitaries?

A necessary and sufficient condition on the unitary $B$ is that its columns all correspond to maximally entangled states. There also does not need to be any relationship between the two unitaries ...
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Why can’t I use quantum teleportation to transmit data FTL 1/4 of the time?

Suppose Alice wants to send Bob a 1000 bit message. To receive the message, Bob flips 1000 coins and writes down the results as 0s and 1s. About 50% of the random bits in the message that Bob ...
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What is the name of this "ancilla based" process to implement gates

This is the circuit on which the magic state model is based. As they say in the linked paper, such a circuit is often called a gadget, more specifically a state injection gadget. The reason why such ...
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Why is a Bell state involved in quantum teleportation?

The motivation for introducing the Bell state is simple: it gets the job done! This of course raises the question: what properties of the Bell state make it suitable for use as a resource in quantum ...
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Can we teleport a human or send information faster than light using quantum teleportation?

In conclusion, NO and NO, respectively. Quantum teleportation does not mean instantaneous disappearance and reappearance of information at another spatial point. Quantum teleportation in plain ...
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Why is measurement needed in teleportation?

measurements in every circuit can be postponed or never performed in a circuit while achieving the same functionality of the circuit That's correct. But if the circuit involves two parties, this ...
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What is the maximum separation between two entangled qubits that has been achieved experimentally?

Photons travel fast, and there's often the option to transfer their entanglement to solid state. Of course, the advantage of transferring entanglement to a solid state qubit is that one is able to ...
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Using a fractional number of classical bits within quantum teleportation

I recently found a paper by Subhash Kak that introduces teleportation protocols that require lesser classical communication cost (with more quantum resource). I thought it'd be better to write a ...
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Generalization for $n$ quantum teleportations

The simplest way to generalize teleportation is to just repeat it. If you have one EPR pair divided between Alice and Bob, teleportation allows you to move one qubit from Alice to Bob (or vice versa) ...
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Quantum teleportation of a state, from one of two bases

Alice receives a quantum state $|\psi\rangle$, which is an element of some basis $\mathcal{B}$, though she does not know what $\mathcal B$ is. She then teleports this to Bob, who is told by someone ...
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Quantum gate teleportation T gate

Think about the following sequence: $$XT^\dagger X=\left(\begin{array}{cc} e^{-i\pi/4} & 0 \\ 0 & 1 \end{array}\right)=e^{-i\pi/4}T.$$ So, that lets us write  TXT^\dagger=e^{-i\pi/4}TTX=e^{...
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In what ways can qubits be used for applications that do not require entanglement?

One (obvious) application is the generation as True Random Number Generators, e.g. IDQ, or you can download some here Free True Random Numbers (please do not use these for security relevant ...
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Understanding quantum teleportation algorithm from qiskit tutorials

Your circuit does not measure $q_2$ qubit after teleportation; I guess that is why teleportation of $|1\rangle$ qubit is shown incorrectly.
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