Questions tagged [ibm-q-experience]
The IBM Q Experience is an online platform that gives the general public access to a set of IBM’s prototype quantum processors. It is an example of cloud-based quantum computing (from Wikipedia). As of July 2018, there are five processors on the IBM Q Experience: two 5-qubit processors, one 16-qubit ...
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How to deal with -LookupError: backend “ibmqx4” is not found?
I am using Jupyter notebook to write and running my qiskit codes (python 3.6)
and every time I encounter the message: LookupError: backend "ibmqx4" is not found, right now the ibmqx4 computer is not ...
4
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How can I get access to IBM Q 20 Tokyo and IBM Q 20 Austin?
How can I get access to IBM Q 20 Tokyo and IBM Q 20 Austin?
In the Q- experience site there is written that the access is for IBM clients only and in the profile there is a "promotional code" that ...
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3answers
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Is there something like GitHub for Quantum Programming?
I'm just learning about quantum computer but some of it has been available for people to research & practice so I'd like to study it myself. The only kind of quantum computing I found so far is ...
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What is the purpose of the TDG gate in QISKit?
The QISKIT documentation doesn't explain what a TDG gate does and I can't find it anywhere else online.
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Is there a common set of modules for user-defining-quantum-gate for QISKit
I am wondering if there exists a common library or a set of modules for user-defining-quantum-gate for QISKit.
If it does, could you tell me?
By referring to Define Quantum Gates and How to define ...
4
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Phase-Shift Gate in Qiskit
How to implement the phase shift gate in qiskit or ibmq?
Phase Shift Gate : $$\begin{pmatrix}e^{ia} && 0 \\ 0 && e^{ia}\end{pmatrix} = e^{ia}I$$
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Controlled-U operation in IBMQ
Suppose we have any matrix in $\mathrm U(2)$ and we need to construct a Controlled-$U$ operation with the $H,T,S$ gates. Then I am aware of the construction given in N&C of decomposing $U$ into $e^...
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Construct Controlled-$G^{\dagger}$ from known Controlled-$G$
Let there be a known a scheme (quantum circuit) of Controlled-G, where unitary gate G has G$^†$ such that G≠G$^†$ and GG$^†$=I (for example S and S$^†$, T and T$^†$, V and V$^†$, but not Pauli and H ...
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Quantum algorithm for linear systems of equations (HHL09): Step 2 - Preparation of the initial states $|\Psi_0\rangle$ and $|b\rangle$
This is a continuation of Quantum algorithm for linear systems of equations (HHL09): Step 2 - What is $|\Psi_0\rangle$?
In the paper: Quantum algorithm for linear systems of equations (Harrow, ...
7
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Changing indices of qubits in QISKit
I was wondering if something like this is possible in QISKit: let's say we have two registers containing target and ancilla qubits:
$a_0$ -------------------
$a_1$--------------------
$\vdots$
$...
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Practical Implementations of QECCs in IBM Q Experience
I am learning how to program the IBM Q Experience quantum computers in order to learn more about how does it work and in order to perform some experiments in it. By doing so I was wondering what are ...
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How to implement the “Square root of Swap gate” on the IBM Q (composer)?
I would like to simulate a quantum algorithm where one of the steps is "Square root of Swap gate" between 2 qubits.
How can I implement this step using the IBM composer?
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Implementation of the oracle of Grover's algorithm on IBM Q using three qubits
I am trying to get used to IBM Q by implementing three qubits Grover's algorithm but having difficulty to implement the oracle.
Could you show how to do that or suggest some good resources to get ...
7
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2answers
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Allowed CNOT gates for IBM Q 5 quantum computer
I trying to do some tests in the IBM Q5 computer of IBM quantm experience for some simple error correction protocols, but as I can see, some operations between the qubits are not allowed.
For example,...
9
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How can a controlled-Ry be made from cnots and rotations?
I want to be able to applied controlled versions of the $R_y$ gate (rotation around the Y axis) for real devices on the IBM Q Experience. Can this be done? If so, how?
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How to delete pending jobs on IBM Quantum Computer to retrieve units?
I am trying to run some code using qiskit, but I get the error message, that I have run out of necessary Experiment Units. I ...
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What would a very simple quantum program look like?
After reading the "first programmable quantum photonic chip". I was wondering just what software for a computer that uses quantum entanglement would be like.
Is there any example of code for specific ...
7
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1answer
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How to explain in layman’s terms the significance of the difference of qubits of the D-Wave and IBM QX?
So, @AndrewO mentioned recently that he has had 'encounters' with people wondering why D-Wave has a lot more qubits than IBM. Of course, this comparison is faulty, since the IBM and D-Wave's machine ...
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There was an error in the circuit!. Error = 'QISkit Time Out'
I've got the following quantum code using QISKit (based on hello_quantum.py):
...
