Questions tagged [teleportation]

Quantum teleportation is a process by which quantum information (e.g. the exact state of an atom or photon) can be transmitted (exactly, in principle) from one location to another, with the help of classical communication and previously shared quantum entanglement between the sending and receiving location. (Wikipedia)

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Explain matrix multiplication math operations of a Hadamard gate after a phase gate

Starting with $|0\rangle$, I would like to understand how the probability values of 85.4% $|0\rangle$ and 14.6% $|1\rangle$ are derived from the payload circuit below? After applying the 45 degree ...
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In what ways can qubits be used for applications that do not require entanglement?

Many good questions on this site have explored how entanglement lies at the boundary between the quantum world and the classical. For example in computational speedups, or teleportation or superdense ...
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How to understand a phase operation between 2 Hadamard gates?

I would like to understand this image, of a "payload preparation" gate. A single H gate will create a superposition, while the phase will rotate 45 degrees. What does the second H gate do in this ...
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How to integrate Simulaqron on ProjectQ

I am trying to simulate quantum teleportation on ProjectQ using simulaqron (enabling me to use quantum internet for teleportation) however I am not sure if my approach is right. In the working paper ...
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Quantum gate teleportation T gate

I am faced with the problem of teleporting certain gates using modified Bell states. For example, I have solved the problem with the $S$ gate, which is defined as following: Alice and Bob share a ...
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Quantum teleportation with “noisy” entangled state

This is actually an exercise from Preskill (chapter 4, new version 4.4). So they are asking about the fidelity of teleporting a random pure quantum state from Bob to Alice, who both have one qubit of ...
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Understanding this description of teleportation

In the context of quantum teleportation, my lecturer writes the following (note that I assume the reader is familiar with the circuit): If the measurement of the first qubit is 0 and the measurement ...
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Quantum teleportation of a state, from one of two bases

I'm watching Christian Schaffner's talk on quantum position-based cryptography (link here) and have a question about a particular application of teleportation. At about the 16:40 mark, he seems to ...
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How to complete this teleportation circuit? How to create a copy of $|\psi〉$?

This is a quantum circuit. M represents the act of making a measurement on the first two qubits. The circuit is supposed to transfer the state $|\psi\rangle = a |0\rangle + b |1\rangle$ ($a, b \in \...
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Are superdense coding and teleportation just a prototype or the 'only' type?

I am interested to know if models in quantum mechanics and techniques like superdense coding teleportation are just single cases where they were found to work. Or rather just a prototype of many other ...
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How to prove teleportation does not violate no-cloning theorem?

For a given teleportation process as depicted in the figure, how one can say that teleporting the qubit state $|q\rangle$ has not cloned at the end of Bob's measurement?
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How we can describe entanglement from measurement and resource perspectives?

When we read books on quantum computing and information theory, specifically in entanglement we find some distinguishability between those who focus on entanglement as a resource or use it as an ...
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Why is measurement needed in teleportation?

One of the postulates of QC is, that measurements in every circuit can be postponed or never performed in a circuit while achieving the same functionality of the circuit (at least this the way I ...
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Can we teleport a human or send information faster than light using quantum teleportation?

What does quantum teleportation mean? Is it something that will allow us to send information faster than the light? Can we teleport a human with it?
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Quantum teleportation with moving Alice and Bob

I have questions regarding quantum teleportation, which keep confusing me. Suppose Alice and Bob are in the same inertial frame $K$, and at time $t$ (in $K$) Alice teleports a quantum state to Bob. ...
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Quantum teleportation over continuous variables?

I came across this circuit diagram for CV quantum state teleportation: Source: Xanadu Strawberry Fields: Docs / Quantum algorithms / State teleportation It was accompanied by a brief ...
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What does teleportation have to do w/ XOR linked lists? [closed]

I am trying to wrap my head around the correlation between repeating teleportation & XOR linked lists. I understand that: "the quantum equivalent of the one time pad (i.e. XORing a message with ...
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Generalizing quantum teleportation for qudits

In an answer to a previous question, Generalization for n quantum teleportations, Craig Gidney states: The more complicated way to generalize teleportation is figuring out how to make it work on ...
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Why can't you run a teleportation circuit on an IBM Q device?

I'm studying teleportation circuits with this tutorial and just out of curiosity, why can't a teleportation circuit be run on an IBM Q device?
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Building a matrix corresponding to the teleportation circuit

I'm trying to build the matrix that corresponds to this quantum teleportation circuit, but it never works when I test it in the quirk simulator, I tried finding the matrix corresponding to every part ...
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What's the matrix representation of this 3 qubit circuit?

How do I calculate the matrix representation of this part of a teleportation circuit? It must be a matrix of dimension 8.
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Why is super-dense coding called the inverse of quantum teleportation?

I am new to quantum computation and I recently came across the statement that super-dense coding can be called the inverse of quantum teleportation
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Quantum teleportation: second classical bit for removing entanglement?

I have read about how Alice can send Bob a qubit $\alpha |0\rangle + \beta|1\rangle$ if they share an EPR pair. This gives an initial state: $(\alpha |0\rangle + \beta|1\rangle) \otimes (\frac{1}{\...
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Qutrit Teleportation

I'm working through Scott Aaronson's Quantum Information Science problem sets, and I'm having trouble with a specific problem in ps5 (PDF). Specifically the following problem: A “qutrit” has the ...
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Generalization for $n$ quantum teleportations

In Breaking Down the Quantum Swap, it is stated: Thanks to the CNOT, we can implement a xor-swap on a quantum computer. All we need to do is chain three CNOTs back and forth. In a comment to a ...
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When you act on a multi-qubit system with a 2-qubit gate, what happens to the third qubit?

I am learning to manipulate Qbits and recently I saw the teleportation algorithm. I read about it in two places: Wikipedia and Lecture Notes from Ronald de Wolf (Page 7, 1.5 Example: Quantum ...
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How the joint state of these qubits is derived?

Can someone show to me the steps to derive the joint state at the bottom of this image, please? I tried to follow his explanation but I didn't get the same results… This is taken from the lecture ...
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Using a fractional number of classical bits within quantum teleportation

Recently, I heard that there can be transfer of rational classical bits (for example 1.5 cbits) from one party to another via quantum teleportation. In the Standard Teleportation Protocol, 2 classical ...
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What is the maximum separation between two entangled qubits that has been achieved experimentally?

Considering two entangled flying qubits, as far as I know, there is no physical limit for separating them without losing quantum information. See: Is there any theoretical limit to the distance at ...
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What is quantum gate teleportation?

Quantum state teleportation is the quantum information protocol where a qubit is transferred between two parties using an initial shared entangled state, Bell measurement, classical communication and ...