Unanswered Questions
594 questions with no upvoted or accepted answers
8
votes
1
answer
410
views
Enforcing a particular layout mapping in Qiskit
I would like to ask how to set a particular layout during transpiling. I guess that the layout can be set by the initial_layout parameter in the transpiler. However,...
CommunityBot
- 1
7
votes
0
answers
210
views
Run VQE for parametrized quantum circuit with ancilla qubits
Let's say we have the following circuit (picture and code shown below), and now the $q_0$ is an ancilla qubit. If the system of interest has only two qubits, Is there a way to use only $q_{1,2}$ as my ...
glS♦
- 26.9k
6
votes
0
answers
278
views
Quantum State Tomography Implementation in IBMQ
I am working to understand quantum state tomography, specifically using the algorithm presented in PRL 108, 070502. This paper is referenced in IBMQ implementations of QST, both in old deprecated ...
6
votes
0
answers
132
views
Writing circuits in Qiskit using only Clifford and T gates
Is there a way in Qiskit to write my circuit using only Clifford and T gates (CX, S, H, T and I think also $S^\dagger$ and $T^\dagger$)? With the function compile (with aer simulator) it gives me some ...
- 3,469
6
votes
0
answers
141
views
Bell State 11 not working for parity curve
I am currently writing a script to automate the creation of parity curves for a 2 qubit bell state and then calculate fidelity and proving entanglement from that (inspired by this paper). It was going ...
glS♦
- 26.9k
5
votes
0
answers
271
views
How to get the compiled circuits and measurements from a Qiskit Runtime job
I have not been able to find any way to retrieve the compiled circuits and the measurement counts used for a Qiskit Runtime job. This page describes the various error suppression mechanisms available. ...
- 726
5
votes
1
answer
718
views
Two qubit gate decomposition using Qiskit
I am writing some python code to be able to optimise the total error in two qubit gate decomposition.
I am using the Qiskit module qiskit.quantum_info.synthesis.two_qubit_decompose
My question relates ...
CommunityBot
- 1
5
votes
0
answers
725
views
OpenFermion to Qiskit
Is there a direct way to go from an object generated in OpenFermion to objects usable in Qiskit? I can't find anything about any plugin.
It's not too hard to translate into pyQuil and then to Qiskit ...
5
votes
0
answers
105
views
Active areas of research for NISQ algorithms
What areas of research in NISQ algorithms have heavy focus? I'm interested in quantum chemistry algorithms because of previous work (e.g. VQEs), and I'd love to learn more about other near-term ...
5
votes
0
answers
160
views
Results from looped experiments on IBM Q different than individual experiments
I'm experiencing an issue while using Qiskit where the counts from a job return vastly different values when ran in a loop or as an array of circuits as opposed to single experiments when run by ...
- 17.8k
5
votes
0
answers
157
views
How can I express controlled unitary operation in QPE of this implementation of HHL?
I have found this implementation of HHL, and I don't understand why the controlled unitary operation is expressed in the form of $\exp(i t_0 A/2)$ and $\exp(i t_0 A/4)$.
The rotation of $\pi$ and $\...
- 17.8k
4
votes
0
answers
60
views
Evaluating expectation values of operators using StateVector and MPS in Qiskit 1.0
Assume one has a QuantumCircuit object and a list of SparsePauliOp. How do I calculate their expectation values using the MPS ...
- 2,221
4
votes
0
answers
94
views
Quantum Phase Estimation for Chemical Hamiltonian
I am working on implementing QPE for calculating the ground state energy of a small molecule like H2 or HeH+. I've written some code that is getting results within about 10% accuracy, but I'm not ...
- 41
4
votes
0
answers
68
views
Failed to load program into HAL component
I'm getting this error message when I execute my qiskit code on one of the available quantum computers of IBM:
...
4
votes
0
answers
183
views
Variational Quantum Eigensolver (VQE) by scipy minimize in cirq does not work
I tried to make a cirq program calculating an eigenvalue of the observable by VQE. Inspired by the qulacs VQE tutorial, I defined a cost function from the expectation value of the observable with ...
- 41