Questions tagged [ibm-q-experience]
Use this tag for questions about IBM's quantum processors which are accessible online. DO NOT use this for questions about general Qiskit issues. As of July 2018, there are five processors on the IBM Q Experience: two 5-qubit processors, one 16-qubit processor and two 20-qubit processors (only available to hubs, partners, and members of the IBM Q network).
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questions
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IBM quantum computers gate delay values
I am doing an state of the art study about the existing quantum computer technologies and one of the parameters of interest is the gate delay value, as it determines the time expected from a gate from ...
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1answer
41 views
Measuring T1 T2 on IBM Q
We’ve been asked to measure relaxation and decoherence times T1 T2 on the IBM Q using the composer only, qiskit not allowed. I’m a bit confused about the way to do it. Can someone explain the idea ...
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4answers
52 views
Implementing four oracles for the Deutsch Algorithm (preferably on IBM Q Experience)
I guess, I understood simple Deutsch Algorithm (if unary function is balanced or constant) as described here: Introduction to quantum computing: The Deutsch algorithm
I need to test it. I was ...
2
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1answer
52 views
How to make a Shor's algorithm for an arbitrary number of qubits with Qiskit on a IBM machine?
So suppose you want to do a Shor algorithm on an arbitrary number of qubits using an arbitrary $a$ (the base number in the periodic function $a^x \mod c$) and $c$ ( the factored number). Making the ...
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1answer
37 views
OPENQASM: How to include my own libraries
I studied the OPENQASM 2.0 spec a few times but failed to find a way to include my own libraries. Have I missed anything?
Right now, the only way is to use ...
2
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1answer
109 views
Why is implementation of controlled Hadamard on IBM Q so complex?
With reference to question how to implement CCH gate I easily realized that CH gate can be implemented with $\mathrm{Ry}$ gates and $\mathrm{CNOT}$ followingly:
Note $\theta = \frac{\pi}{4}$ for ...
1
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1answer
41 views
IBM Quantum Experience API Without QISKit
I am a computer science master's student who is doing research in the field of quantum computing. I have an IBM quantum experience account(https://quantum-computing.ibm.com/) and as such I was ...
4
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2answers
87 views
How to implement the CCH gate in quantum computers available in clouds?
How to implement CCH gate in quantum computers available in clouds? If there is not any gate directly available for it, what are the possible ways to represent CCH?
4
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1answer
94 views
What is the state of the art on Quantum Random Access Memories? [duplicate]
I realized that Quantum Random Access Memory (qRAM) was proposed to make quantum computers more similar to classical one. Currently quantum computers have very constrained memory, given only quantum ...
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2answers
68 views
Qubit measurement is followed by instructions. Error code: 7006 [duplicate]
Trying quantum teleportation in
https://github.com/Qiskit/qiskit-textbook/blob/master/content/ch-algorithms/teleportation.ipynb
Succesful runs in 'qasm_simulator', but when switching to IBMQBackend('...
3
votes
2answers
130 views
Cannot replicate results in article on pricing financial derivatives on IBM Q
I am trying to implement a circuit for searching for the largest eigenvalue and respective eigenvector of an operator, i.e. phase estimation, introduced in article Towards Pricing Financial ...
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2answers
974 views
Changing one qubit causes changes in another independent qubit on ibmqx2 in IBM Q Experience
When I run this program on ibmqx2 (the backend matters) in IBM Q Experience, the results are interesting. Essentially, the program measures the error rate on $|q_0\rangle$ after fiddling with $|q_1\...
3
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1answer
60 views
Writing twice to same classical register -> 1 for some backends in IBM Q Experience
On some backends, measuring the same expected value twice to the same classical register always leaves that classical register in the "1" state. I don't know if these results will hold over time, but ...
5
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1answer
141 views
Reversal of time arrow on IBM Q
It is well known that a quantum computer is reversible. This means that it is possible to derive an input quantum state $|\psi_0\rangle$ from an output $|\psi_1\rangle$ of an algorithm described by a ...
2
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2answers
89 views
Simple program produces consistently skewed results in IBM Q Experience
I'm running this program (essentially a two bit random number generator) on ibmqx2 in IBM Q Experience. The backend matters. Other machines give unexpected results, but the graph looks different for ...
3
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2answers
95 views
Why IBM devices have the same number of qubit and the same architecture, but the error rates are different?
Here are two different IBM quantum online devices,
Both of them have the 5 qubits and the same architectures.
But why do they have different error rate?
What's the different between them?
2
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1answer
83 views
How to plot histogram or Bloch sphere for multiple circuits?
I have tried to plot a histogram for the multiple circuits for the code given below. I think I have done it correctly but don't know why it's not working. Please help me out. If possible please solve ...
0
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1answer
50 views
run() got an unexpected keyword argument 'seed'
I am new in quantum computing. I was going through the user guide of IBM Q so I was just trying to run the python code they have provided at the end of this page enter link description here while ...
1
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1answer
43 views
Job Status: job incurred error
I was checking the limits of shots in IBMQ at the time of execution of the circuit so I was getting this error message Job Status: job incurred error at ...
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1answer
76 views
Why qiskit superconducting device native gates different from that of trapped ion device?
For IBMQ device based on superconducting technology, when we transpile the circuit, it is decomposed of U1,U2,U3 and CNOT gates, which are its native gates.
However for trapped ion device, its native ...
2
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1answer
69 views
Custom gates on IBM Q
I realized that QASM supports custom gates. However, when I tried to create the gate, transpiling error appeared both on simulator and real quantum processor. I suspect that IBM has not implemented ...
1
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1answer
139 views
How to fix an error: AttributeError: 'IBMQFactory' object has no attribute 'get_backend'
when I tried to execute task in "Jupiter notebook" in the IBM Q experience (the browser),
...
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1answer
29 views
How does number of shots (number of times the computation is repeated) affects time complexity [closed]
I want to know what happens to the time complexity in terms of big O analysis
0
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1answer
58 views
QISKit Connection
I ve beeen trying to use the qiskit package from spyder IDE inisde anaconda (Python version 3.7) but when i try to acces my account I get the following error:
...
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1answer
57 views
IBM Q experience - error code 520
I have been running a variational circuit optimizing the parameters on the "melbourne" device. The system launches multiple jobs in parallel, and only gets the jobs accepted that my credit allows. The ...
0
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1answer
53 views
Find the Q-Experiment tutorial for beginner
Where I can find the previous Quantum-Experiment tutorial for beginners?
(the one that was under https://quantumexperience.ng.bluemix.net/qstage/#/account)
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1answer
102 views
What does the error rate on the IBMQ website mean？
How is the error rate pointed by the arrow defined? How did you get it?
thanks!
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1answer
62 views
What can be done so far with cloud quantum computing?
As a developer myself, I still do not understand what can be done so far with services like AWS BRAKET or IBM CLOUD QUANTUM COMPUTING.
Can someone explain me the practical purpose of it in the present?...
2
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1answer
59 views
Is there a way to output a circuit from Qiskit to the IBM Q Experience circuit composer?
I can't seem to find anything, but this seems like something that should be possible.
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0answers
53 views
Ripple Adder using Full Adder [closed]
I have been trying to implement a ripple carry adder using qsikit in IBM Q Experience. I was able to implement full carry adder but I am having trouble with ripple carry adder. I am able to add 100 + ...
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1answer
61 views
Can't access IBMQ (NameError: name 'IBMQ' is not defined)
When I type this: IBMQ.load_account(), I am getting this error. What does this mean, and how can I rectify it?
...
2
votes
1answer
90 views
Couldn't connect to IBMQ server
When I access IBM Q backend with qiskit code, an error occurs.
from qiskit import IBMQ
qt = 'xxxxxxxxx'
IBMQ.save_account(qt)
IBMQ.load_accounts()
The error ...
3
votes
1answer
132 views
How to put a quantum computer on the cloud?
What are the infrastructures needed to build a cloud quantum computing service like IBM Q Experience?
It seems this is not a trivial task. IQX has been running for more than 3 years and yet it is ...
0
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0answers
47 views
What is the URL of the result?
This answer states that:
Once it is submitted, your job will be in queue. You will have to request by GET this job ID to get the answer from the backend.
The GET URL is: https://quantumexperience....
3
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2answers
316 views
Explanation of output produced by the following quantum circuit
I've recently started reading about quantum computing and I apologize in advance if this is (and I think it probably is) a very simple question.
I've created the following circuit.
I believe I ...
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1answer
62 views
Bernstein-Vazirani algorithm in IBM Q Experience [closed]
I have composed the gate with IBM Q Experience, but I do not know how to set the answer.
Please tell me how to set it?
4
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0answers
36 views
Vary parameter between shots
Is it possible to tell Qiskit to execute a parameterized gate where the parameter varies between shots?
Let's say, for whatever reason, I'd like to speed up the dephasing of a qubit during a run. I ...
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1answer
36 views
qiskit - Creating your own ExperimentResultData object
Could someone guide me on how to create my own qiskit.result.models.ExperimentResultData object? I would simply like to create an object with some self-created dict ...
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1answer
27 views
Data file read/write from within IBM Q-Experience Jupyter notebook
In IBM Q-Experience how can I upload a data file that I intend to read from the python code?
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2answers
58 views
Bell state: simultaneous measurement of two entangled qubits
What will happen if the two qubits in Bell state for a 2-qubit system, $\frac{1}{\sqrt2}(\left|00\right\rangle+\left|11\right\rangle)$ are simultaneously measured at the same instant? Two scenarios: ...
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1answer
75 views
How to get more credits? [duplicate]
How can I have 150 or more credits?
I mean I want to have '150/150 credits'.
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0answers
28 views
IBM Circuit Composer pane is blank
I'm new to IBM Quantum Experience. When I initially create a circuit using the composer, all is well, but when I save the circuit and open it again, the composer window is blank - no gates or wires. I ...
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0answers
31 views
Implementing B92 protocol on IBM Qx
I wanted to implement the B92 protocol on IBM Qx. Implementing the protocol would require that a particular qubit should not be measured when using a particular base i.e. there should be no output at ...
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0answers
55 views
Many jobs hanging after creating
I am running a VQE calculation running from a cluster using nohup.
However, some of my jobs keep hanging with 'creating' and therefore my VQE is not converging/not working.
However, at the same time,...
2
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0answers
22 views
Tensored vs ordinary measurement mitigation runtime
My experiments show that the runtime of actually applying the measurement filter matrices to circuit execution results is much slower for tensored mitigation than ordinary mitigation. Tensored ...
4
votes
2answers
551 views
Trying to build a circuit for quantum teleportation on IBMQ I get ERROR_RUNNING_JOB error
I am trying to build a circuit for quantum teleportation. On the simulator, everything runs fine and according to expectations, however, I am not able to run the algorithm on the real quantum ...
2
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0answers
87 views
Problem with measurement error mitigation using VQE
I am attempting to mitigate measurement error while running on one of IBM's real devices and am doing so by passing CompleteMeasFitter into ...
1
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1answer
75 views
Attribute error in Qiskit
Tried executing plot_histogram(result.get_counts(circuit))
where result has the job result and circuit is the Quantum circuit
But an attribute error hits every ...
2
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1answer
44 views
Existing measurement error mitigation
Does IBM compute a measurement error mitigation calibration matrix that can be accessed from its device properties or somewhere else? Or does the user have to do that every time?
2
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1answer
66 views
Error on loading account with qiskit: “TypeError: __init__() missing 1 required positional argument: 'url'”
We are using an open account.
We can not load the account even when we use the code on new notebook.
The error message is:
...
