All Questions
9
questions
1
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1
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97
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Is this quantum circuit design more prone to noise?
I am designing a quantum circuit which uses one qubit as the control of many $\text{CSWAP}$ operations. And then, this qubit will be measured.
Will the result be more prone to noise since all the ...
- 121
1
vote
1
answer
159
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How to fix two flip-bit errors in a 3 qubit input
Aware of how a 1-bit flip can be fixed for 3-qubit input by having 2 Ancilla bits, encoding, and using the Toffoli gate to fix the error and decode. How can this idea be extended for a 2-bit flip (...
- 69
1
vote
1
answer
239
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Get parameters of a CU gate for implementing an erroneous CX gate with fidelity = 0.81
Let's say the definition of an erroneous CNOT gate is given as - CNOT is a 2-qubit quantum gate when the control qubit is at state 0, applies identity operation on the target qubit, when the control ...
- 69
0
votes
1
answer
134
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How to apply error-correction to the swap test circuit?
Swap test is a simple quantum circuit to measure the inner product of two quantum states [Wiki: swap test], it only contains three quantum gates. However, due to the error in the real quantum computer ...
- 365
1
vote
1
answer
52
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How to best represent 5-Qbit codeword operator in Qiskit [duplicate]
We learned that in the 5-Qibit error correcting code, the logical zero state $ | \bar{0} \rangle $ is encoded in the form of $ \frac{1}{4} (\mathbb{1}+M_0)(\mathbb{1}+M_1)(\mathbb{1}+M_2)(\mathbb{1}+...
- 599
4
votes
1
answer
510
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How the real IBM quantum computers apply arbitrary Rz(θ) gate rotation? [closed]
I want to ask the following questions:
(1) The basis gate set of IBM quantum computers is { Id, Rz(θ),√X, X, CNOT, reset}. Somebody said that IBM didn’t really apply Rz(θ) gate on the machine. The ...
- 95
5
votes
1
answer
206
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Where does the "correction" in quantum error correction occur, specifically when using repetition codes?
I'm reading the part of the qiskit textbook that deals with this (https://qiskit.org/textbook/ch-quantum-hardware/error-correction-repetition-code.html) and so far it seems as though they're just ...
- 103
1
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1
answer
724
views
Applying a projector to a qubit in a qiskit circuit
I'd like to be able to apply $|0 \rangle \langle 0|$ to project a qubit to the state $|0 \rangle$ in the middle of qiskit circuit (see, for example, the attached circuit).
I wonder if, in general, ...
- 25
0
votes
1
answer
145
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Is there a way to entangle to a dirty qubit?
Let's say I do something to a qubit, and I want to entangle it to a 2nd one, like this:
...
- 584