Unanswered Questions
355 questions with no upvoted or accepted answers
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Procedure for constructing magic state gate injection gadgets
I have a quantum computer that cannot implement the gate $U$ by itself, and needs help in the form of a magic state $|U\rangle$ held in another register. Is there a general-purpose procedure for ...
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44
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Operation 'sx' is not defined for this system
Any one knows how to resolve the below error:Operation 'sx' is not defined for this system. The below code works really well with ...
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How to train QNN on qiskit or ionq simulators
I am trying to train a QNN using qiskit and ionq, the method I use now is to manually feed my input data into quantum circuits:
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How to entangle two separate set into one?
I have two sets of qubits where the information is encoded in amplitude. How can I entangle them into one to save qubits.
The information $k_0,k_1,k_2,k_3$ and $k'_0,k'_1,k'_2,k'_3$ are encoding in ...
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Implementing the "Inplace Access to the Surface Code Y Basis" with neutral atom/shuttling platforms
I am currently trying to understand this paper: https://arxiv.org/abs/2302.07395. I understand that the goal is to move the twist around to perform the Y measurement/phase gate. I see the step by step ...
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Proof of Hadamard transform on $N$ qubits
Q:$$H=\frac{1}{\sqrt{2}}(|0\rangle\langle0|+|1\rangle\langle 0|+|0\rangle\langle 1|-|1\rangle\langle 1|)$$
Show that
$$ H^{\otimes N}=\frac{1}{\sqrt{2^N}}\sum_{x,y\in\{0,1\}^N}(-1)^{x\cdot y}|x\rangle\...
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How to get historical calibration data for mthree (M3) from IBM Quantum devices?
I'm using mthree in Batch mode. A batch needs to be queued before it can be executed. The time when a batch was executed can be obtained from the IBM Quantum Platform site, so I would like to obtain ...
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How much information can be transferred via a given 2-qudit gate?
Suppose Alice and Bob want to send some (classical) information to each other via the following scheme: there is a quantum system consisting of 2 qudits $A$ and $B$ (both have dimension $d$), with ...
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Apply parametric gate to quantum state in symbolic tensor representation
Suppose I am given a $n$-qubits statevector $|\psi\rangle$ and a single-qubit parametric gate $G_i(\theta)$ to be applied on qubit $i$. I want to implement from scratch a Python function to apply the ...
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Quantum oracle based on MCX gates
I am working on a quantum implementation of a fuzzy inference engine. This system is based on a quantum oracle which fulfills the reconstruction of the rule base. In the current implementation (image ...
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quantum circuit for 0-1 matrix
Given a $0-1$ $2^n*2^n$ matrix, each row has only one 1
each column has only one 1.
Such an unitary matrix can be described by an invertible function $f(x) : [1,2^n]\rightarrow [1,2^n]$, Given such a ...
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Quantum register for variable store - how to encode operations?
Suppose I have a lot of classic variables of a certain number of bits in size, say, 8 bits. Instead of starting each variable from zero in superposition, I want to use the exponential space to encode ...
- 171
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4- controlled- Z gate (C4Z gate) formation using C4X and Hadamard gates
I require a quantum circuit that utilizes C4X and Hadamard gates to form a C4X gate. Could anyone please help me?
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Issue with collecting state tomography data
I am having a problem with collecting state tomography data. When I am running the below code, I get the error: AttributeError: 'list' object has no attribute 'num_qubits'
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What to do about operator scalability?
Suppose I have a 32 qubit register meant to represent a classic variable. I want to apply gates to it and naturally I have to tensor product up to a 32 bit register. That means something like
$$
I_{1} ...
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