# Tag Info

### Where can I find runtime of ibm quantum gates?

You can find the gate length from the backend properties: ...
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### Finite subgroup of $U(4)$ containing a non-Clifford gate and all local Cliffords

No. There is no way to add a non Clifford gate to the local Clifford group $Cl_1^{\otimes 2}$ and get a finite group. Definitions: A subgroup $G$ of $GL_n(\mathbb{C})$ is reducible if we can ...

### The relationship between number of shots and performance of quantum agent

I bet you already have looked this over, but here is the documentation for QASM sim: https://qiskit.org/documentation/stubs/qiskit.providers.aer.QasmSimulator.html There is a command to do the max ...
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### Clarification about QTF proof regarding equality of QFT application and circuit application

I suppose there are two sources of confusion here -- one is the reversed order of the qubits between the circuit and the unitary, and the other is the use of $x$. In terms of qubit ordering, I think ...
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### Definitions of a quantum circuit's depth and connectivity

I would like to give explicit definitions of the circuit depth and connectivity. I assume that the meaning of terms like vector state, quantum circuit, wires, and 1- and 2-qubit gates is understood. I'...
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### Definitions of a quantum circuit's depth and connectivity

The traditional definitions of classical Boolean circuits work perfectly well here: https://en.wikipedia.org/wiki/Boolean_circuit. This is the definition that gives you Niel de Beaudrap's definition. ...
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### Composing the CNOT gate as a tensor product of two level matrices

Although $CNOT$ cannot be written as $A\otimes B$, it can be written as a sum of such terms. For example: $CNOT=I\otimes I +\frac12Z\otimes I+\frac12 I\otimes X - \frac12 Z\otimes X$.

### Definitions of a quantum circuit's depth and connectivity

Let me try to provide a more precise definition of connectivity in a quantum circuit. Every quantum circuit defines a graph (network), with vertices (nodes) given by qubits. There is an edge $q_1 q_2$ ...
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### Controlled phase shift gate

The phase shift is a family of single-qubit gates that map the basis states ket(0) to ket(0) and ket(1) to exp(i theta)* ket(1) so by using this we can find matrix of controlled phase shift operator....
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### How to write a code to separate two qubits?

Maybe it should be useful tu use qutip to better understand what you desire (if you are familiar with python) by visualizing exactly the 2 qubits and its state vectors (which I believe is what you ...
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### I am getting an error like this 'Invalid input data format for Statevector'

Tips for you to understand error: take a look at qiskit docs, what is the valid data input, learn more about Statevector class https://qiskit.org/documentation/stubs/qiskit.quantum_info.Statevector....
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### Is there a quantum gate that can turn any superposition $|\varphi \rangle$ into a unit column vector $|00\cdots 1\cdots 0\rangle$

It depends on what you mean. For a given state $|\varphi\rangle$, it is always possible to find a gate $U_\varphi$ such that $U_\varphi|\varphi\rangle=|i\rangle_{10}$ for some given $i$. However, it ...
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### How can I write if conditions on quantum registers using qiskit

If "some operations" in your question means quantum operations, then you can use Gate.c_if() to apply a gate based on a value in a classical register as ...
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### Speed of Superconducting Qubit Architectures

Google's Sycamore processor for which they claimed quantum supremacy (https://doi.org/10.1038/s41586-019-1666-5) performs two-qubit operations in 12 ns, so that would be some 80 MHz. Of course ...
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