Questions tagged [ibm-q-experience]
Use this tag for questions about IBM's Quantum Service - Circuit Composer & Quantum Lab. DO NOT use this for questions about general Qiskit issues (use [qiskit] for that).
449
questions
2
votes
2answers
38 views
IF statement in OpenQASM2.0 on IBM Quantum Experience — error
I have written the following toy .qasm file, which has some adaptive measurements:
...
3
votes
1answer
38 views
How do I identify a VQE job run in real hardware?
I am running a VQEUCCFactory for H2 on a real hardware device.
...
1
vote
1answer
58 views
Guide for Qiskit's Measurement Error Mitigation?
I'm reading about error correction mainly in the Qiskit Measurement error mitigation chapter contains what it seems and easy way to "clean up" the noise obtained in the IBM (or NISQ) devices....
3
votes
1answer
146 views
How do I send a quantum circuit to IBM for execution?
I have, let's say, the following quantum circuit:
The QASM code of this quantum scheme has the following form:
...
3
votes
0answers
159 views
+100
Apply readout error mitigation to mid-circuit measurement
Here's the quantum circuit I'm constructing:
...
2
votes
1answer
53 views
QPE Circuit test on Quantum Computer ('ibmq_16_melbourne')
After several atempts, I cannot mitigate the error when running the code on a NISQ, via the qiskit library (more specifically on the 'ibmq_16_melbourne').
I've already mapped the connected qubits and ...
3
votes
2answers
363 views
How can I specify the qubits on quantum computers that I want to use?
Suppose I have the following 2-qubit quantum circuit:
...
2
votes
1answer
27 views
“us” units on relaxation times $T_j$ in the IBM backends
A pretty lame question but, the backends relaxation times $T_1,T_2$ are given in us units. What are those? (Frequencies are given in GHz... Is it really $\mu s$ but IBM can't display the $\mu$ in the ...
1
vote
1answer
23 views
$T_1/T_2$ thermal relaxation example
The built in noise models in Qiskit have an example of $T_1/2T_2$ relaxation here. I have a couple of doubts; the notebook is not very clear in some of the steps.
Why does one need $T_2\leq 2T_1$? ...
1
vote
2answers
81 views
Qiskit Pulse Notebook
When I downloaded the source code from Qiskit Notebook Accessing Higher Energy States and tried to execute it, the output and graph seem wrong in the step finding the frequency step which leads to the ...
2
votes
1answer
62 views
IBM Quantum API for Java Developers
As far as I know, IBM Quantum provides two types of APIs: one for Qiskit, and the other for third-party uses (API for developers).
In this question, there are several arguments about using the API for ...
3
votes
2answers
66 views
Data embedding using IBM quantum composer
How do you use the IBM quantum composer to encode some data $(a,b,c,d)$ represented by a vector ket in which $a,b,c,d$ have been normalized to one? $a|00\rangle + b|01\rangle + c|10\rangle + d|11\...
1
vote
0answers
37 views
issues running a 32 qubit grover's algorithm
I have a 32 qubit grover's algoritm however whenever I run it on the simulator that IBM offers it always ouputs a probability of 1 on every single result.
Is there a way to run circuits larger then 32 ...
1
vote
1answer
44 views
Qiskit Portfolio Optimization : Does the resulting matrix show the stock combination to select?
The IBM Qiskit Portfolio Optimization sample finally provides an array similar to [1,0,1,1] representing the 4 digits as the stocks. So does the ...
1
vote
1answer
67 views
IBM quantum computer giving the wrong result?
This is the first time I am using the IBM quantum computer. I tried to run a circuit (see below the first picture) but the results I got don't match the theoretical results shown (see below the second ...
2
votes
1answer
43 views
Time result for my algorithm
I've used the function result.time_taken to know the amount of time used to execute a task on the real chip, but I don't understand if the result is in seconds or ...
2
votes
2answers
48 views
Who is responsible for implementing quantum error correction?
There are various options for error correction. For example, the Shore code or a whole class of surface codes.
But I don't really understand at what level they should be implemented.
For example, I ...
1
vote
1answer
29 views
How to import circuit libraries into qiskit
Im trying to put the QFT circuit in my qiskit circuit but im having trouble:
...
0
votes
0answers
51 views
How to simplify a circuit with repeated same parts?
If I have a circuit with 3 qubits and repeated gates as follow:
...
2
votes
1answer
83 views
Is RYY gate not available in IBM Quantum Composer?
If so, why? How to create the RYY-gate in the composer?
2
votes
1answer
61 views
Qiskit: Transpilation and the CircuitSampler
I am using Qiskit's opflow and its CircuitSampler to evaluate matrix elements / expectation values. Now, going beyond ...
2
votes
1answer
64 views
Qiskit logical to physical qubit mapping
I want to run a simulation using qasm with a realistic noise model from a backend, specifying a coupling_map as well as an ...
1
vote
1answer
58 views
Is there any way to obtain the number of qubits of a given backend in Qiskit?
I'm testing out a program in different IBMQ mock backends, and I want the program to use the maximum number of qubits in each case. Is there any function/method to extract the number of qubits of a ...
3
votes
1answer
34 views
Is there a way to run “in the background” code sent to the IBM backends?
I use different qiskit backends to run my code. Since the maximum number of shots is $2^{13}$, sometimes I need to send the same code several times with a "different ticket". I am wondering ...
3
votes
2answers
261 views
Drawing the circuit in Qiskit - how to set same style as in Composer?
A quantum circuit can be visualized in Qiskit with circuit.draw. A drawing style can be set with parameter output which can have ...
3
votes
1answer
70 views
Why does running my circuit on Quantum Hardware produce such unexpected resultss?
I am using Jupyter Notebook with Qiskit.
I have created a program that can add two 3-bit numbers together. When I simulate this program on a qasm_simulator it works as expected and I can add any two 3-...
2
votes
1answer
77 views
Why I am gettting this error when I try to open the Quantum Lab in the IBM Quantum experience?
I am using quantum labs in IBM Quantum Experience to my circuits. But from yesterday onwards (May-03-2021) this error message is being shown on my screen. Does anyone have any idea about this issue?
2
votes
1answer
36 views
What is the relationship between the (sx) error rate listed in calibration and the angle/amplitude errors calculated using the fitter?
The IBM Quantum services website lists calibration statistics for their devices, including the (sx) error rate per qubit, which is listed as a single number. One can also manually calibrate a device ...
2
votes
1answer
43 views
Can I use the same qiskit account on two laptops?
I have two laptops with different accounts of Jupyter Notebook. I'm wondering can I use the same qiskit account (with the same token) on both laptops? I'm worried that if I run the token on my new ...
3
votes
1answer
69 views
Why does applying a Hadamard gate three times to $|0\rangle$ result in a tiny imaginary component in the $|1\rangle$ amplitude?
I'm using qiskit with the online IBM Quantum Lab and when I run the following code
...
0
votes
1answer
50 views
4Q Grover circuit working in simulator, however producing nonsense in actual quantum computer
I am a noob at quantum computing but I am certain the circuit is correct. I've tried increasing the number of shots, changing the quantum computer. I think it might be a problem with my ccccx gate? I ...
4
votes
3answers
99 views
What is the difference between Bloch's sphere and IBM's Q-sphere?
I'm new to Quantum Computing and I've been trying to understand single-qubit operations, quantum phases etc through Bloch's Sphere visualization. However, in IBM's Circuit Simulator, they seem to be ...
1
vote
0answers
41 views
Understanding the heavy output problem [closed]
In this paper (or more pedagogically here) it is given a way to compute the Quantum Volume of a quantum computer (qc), specifically aimed at the IBM qcs.
In all this process I found some dark spots ...
3
votes
0answers
44 views
What is the actual precision of the IBM quantum computer?
In working with the IBM quantum computer, one can use for example the composer in order to build simple quantum algorithms. Essentially, one usually feeds a phase in order to affect one of the qubits. ...
1
vote
1answer
49 views
Can I use Quantum lab during IBM Quantum certification exam? [closed]
Hello I am about to take the IBM Quantum Qiskit dev exam. I don't know if I can use the quantum lab (Qiskit) during the exam. Does anyone know?
1
vote
1answer
82 views
Why is a 15-qubit IBM quantum computer not working correctly?
I just wanted to implement an algorithm for adding two 2-bit binary numbers. And it works, but only on an IBM 32-qubit simulator. And on a real 15-qubit computer, ibmq_16_melbourne, it produces very ...
1
vote
1answer
31 views
Recover backend information in working remotely with the IBM-QC
I'm reading the details of qiskit following this paper (I know it's a little bit dated, but some things shown there should be in principle still accessible). For ...
7
votes
2answers
993 views
Characteristics of the IBM quantum computer
On the IBM Quantum Composer website, there are characteristics of qubit computers. For example, ibmq_16_melbourne.
But there is no description anywhere of what:
...
4
votes
0answers
40 views
Adding team to our IBM Quantum Experience account
I have an account and API token on IBM Quantum Experience (https://quantum-computing.ibm.com/)
I would like to add team members to the account, so that everyone can use it without sharing login ...
1
vote
0answers
43 views
IBM Quantum: 20 minutes for 1 shot, timeout for 2 shots. Why? [closed]
It takes 20 minutes for the ibmq_qasm_simulator to execute 1 shot of my circuit. Successful always.
It always times out for 2 shots of the same circuit on the same simulator.
One may assume the ...
0
votes
1answer
41 views
I can't see the results of my of my jobs
New user here. I tried to run a test circuit which I submitted to ibmq_santiago to run, but now I cannot see my results. No histogram, no circuit, only the status timeline. I believe the problem is ...
1
vote
1answer
63 views
How to upload our dataset using pytorch when it is not present in torchvision?
I am trying to upload my dataset(SWELL-KW) instead of MNIST in "Hybrid quantum-classical Neural Networks with PyTorch and Qiskit" provided by IBM qiskit but it says ...
1
vote
1answer
72 views
What is the largest number factored by the IBM Quantum simulators?
Though a lot of papers talk about the largest factored number by Shor's Algorithm, I want to know the largest one factored by the IBM Quantum, for example, the simulator_mps. I am able to use it to ...
3
votes
1answer
108 views
2
votes
2answers
45 views
What is the minimal delay between gates on IBM devices?
Suppose I create the very simple circuit
OPENQASM 2.0;
include "qelib1.inc";
qreg q[1];
x q[0];
barrier q[0];
x q[0];
and submit it to an IBM backend. ...
1
vote
0answers
29 views
IBM Quantum “Jobs” web page problem: “Tags” always missing
I tried to edit the tags and saved them, but the "Jobs" page displays empty tags always. Is that a bug? Did I do it incorrectly?
0
votes
1answer
76 views
Please help interpret the IBM Quantum error code: “Instruction bfunc is not supported [7001]”
I have already run the circuit on the IBM Quantum simulators successfully. But, when I ran the same circuit on the real quantum device ibmq_16_melbourne, I got the error. The IBM website does have the ...
1
vote
1answer
51 views
In the job tab, no histogram appears
(Newbie here) Accessing IBM Q Experience on a Windows 7 operating system and using the Google Chorme browser. I can completely assemble my circuit, using the IBM Quantum Composer and when executing it ...
3
votes
1answer
69 views
How to read a Q sphere representation?
I'm trying to understand the Q-sphere representation of a 3-qubit system. I get that the 3-qubits are in a superposition of 2 different states. The first qubit (rightmost) is in a superposition of <...
1
vote
1answer
61 views
Uploading 20,000 lines of code to IBM Quantum Composer stalls
It is a simple 5 bit circuit, but it has 20,000 lines of QASM code. I try to put it in the composer, but the "Saving..." beside the file name will stay there for hours. I never saw its ...
