All Questions
Tagged with error-correction entanglement
24
questions
11
votes
5
answers
938
views
What is quantum entanglement, and what role does it play in quantum error correction?
I want to understand what quantum entanglement is and what role does it play in quantum error correction.
NOTE:
As per the suggestions of @JamesWootton and @NielDeBeaudrap, I have asked a separate ...
- 251
10
votes
0
answers
102
views
Entanglement-assisted hashing bound for asymmetric depolarizing channels
I reading the paper EXIT-Chart Aided Quantum Code Design
Improves the Normalised Throughput
of Realistic Quantum Devices, which proposes the use of QTCs in order to do quantum error correction for ...
8
votes
1
answer
1k
views
What is the definition of Bell state on a n-qubit system?
Question 1: The bell state for a 2-qubit system has been defined in Neilsen and Chuang's book as the set of maximally entangled states spanned by $\{|00\rangle + |11\rangle, |00\rangle - |11\rangle, |...
- 81
4
votes
1
answer
409
views
How to limit the error probability in large scale quantum computers
I am quite stumped by the fact that the roadmaps for quantum computers as given by IBM, Google, IonQ, etc. seem to imply a linear/exponential growth in the size of their quantum computers.
Naively, I ...
- 220
4
votes
1
answer
1k
views
What are the typical gate times for single-qubit and 2-qubit gates for ion trap, superconducting, neutral atom, photonic, spin QC?
What are the typical gate times for single-qubit and 2-qubit gates for
-- ion trap,
-- superconducting,
-- neutral atom,
-- photonic,
-- spin
quantum computers based on today's technologies?
- 365
3
votes
3
answers
261
views
In the three-qubit bit flip code, why can the first bit flip without impacting the entanglement with the other qubits?
The principle of the three-qubit Bit Flip Code is straight forward at first sight. Using CNOT you basically encode
$$a|0\rangle + b|1\rangle $$
to
$$ a|000\rangle + b|111\rangle$$
using ...
- 151
3
votes
1
answer
182
views
Understanding entanglement distillation via stabilizer codes?
I am having some trouble understanding the distillation of EPR pairs using a stabilizer code. This idea goes back to the paper by Bennet, DiVincenzo, Smolin, and Wooters.
The idea (I think) is that $k$...
- 2,111
3
votes
0
answers
161
views
How does Teleportation based Error Correction (TEC) detect and correct loss/erasure errors?
I'm looking at papers like Demonstration of teleportation-based error correction in the IBM quantum computer (page) 10 and Role of syndrome information on a one-way quantum repeater using ...
2
votes
2
answers
104
views
The behaviour of ebits in Entanglement-assisted Quantum Error Correction Codes?
I am reading about Entanglement-assisted Quantum Error Correction Codes from Quantum Information Processing and Quantum Error Correction: An Engineering Approach (Chapter 9) . It is a scheme that ...
- 822
2
votes
1
answer
176
views
Repetition code encoder circuit
The repetition code encodes $\vert \psi \rangle = \alpha \vert 0 \rangle + \beta \vert 1 \rangle \rightarrow \vert \psi \rangle = \alpha \vert 000 \rangle + \beta \vert 111 \rangle$ using the ...
- 822
2
votes
1
answer
253
views
Is there a way to perform a defect-free logical CNOT on the toric code?
I was curious to whether the two logical qubits on the toric code can be entangled through, for instance, a logical CNOT operation. However, I cannot find any information on this, only how you can do ...
- 99
2
votes
1
answer
455
views
Why doesn't reading the ancilla qubit in Quantum Error Correction kill entanglement?
In Quantum Error Correction we have ancilla qubits (in gray) that will be entangled with the pair of bits we want to check.
Because we don't want to directly measure the "main" qubits (in ...
- 209
2
votes
1
answer
333
views
How many physical qubits are needed to encode a logical qubit on ion trap, superconducting, neutral atom, photonic QC?
How many physical qubits are needed to encode a logical qubit on an
-- ion trap,
-- superconducting,
-- neutral atom,
-- photonic,
-- spin
quantum computer based on today's technologies?
- 365
2
votes
1
answer
49
views
Can we perform teleported-error-correction with noisy Bell pairs?
It is well-known that in https://arxiv.org/abs/quant-ph/0312190 that error correction can be performed by teleportation on the logical level, so prepare one logical Bell pair and (logical?) Bell ...
- 386
2
votes
1
answer
85
views
Kind of errors on entangled states
I see on this chapter that, when noise applies to an even number of entangled qubits, such noise can be considered as operating only on half of those qubits. This is interesting, but I'm not sure if I'...
- 1,998