All Questions
Tagged with ibm-q-experience ibm-q-experience or
675 questions
1
vote
1
answer
1k
views
How to draw CCZ gate in IBM Quantum composer
How to draw CCZ gate in IBM Quantum Composer? There is no CCZ gate in quantum composer.
In addition to this, please help me to draw the gate shown in below figure in quantum composer.
- 587
0
votes
2
answers
117
views
Why after breaking the entanglement does the phase disk in the second qbit not match the result?
I am new in IBM composer quantum and I have a doubt.
I have the next circuit
After reinitializing q0 and reading it. (breaking entanglement) The phase disk for qubit q1 says that 100% is 0, but the ...
1
vote
0
answers
49
views
Copying a reduced noise model from an IBM device
I need to use the noise model coming from a large IBM device. Nonetheless, I do not need to use the whole Noise Model. I only need the information of let's say qubits [10:15] and [20:25]. That would ...
2
votes
2
answers
146
views
Where are the multi-qubit openpulse computers?
As the question says, I'm looking to run some pulse schedules on quantum computers. Right now, I'm really only able to find ibmq_armonk (from IBM) to be an openpulse computer that I am able to use. I'...
- 81
1
vote
0
answers
72
views
How to send another job to a device before finishing the last job?
Is there any way to create a for loop that would send a few jobs to run on a quantum computer simultaneously? I tried:
...
- 11
1
vote
1
answer
60
views
What is "time in system" for a given job and how to retrieve?
I noticed that there is "time in system" for each job.
For example:
I was wondering what does this mean? I am guessing this means the time of the first shot starts on the quantum devices ...
- 11
0
votes
1
answer
484
views
How to get statevector of qubits after running quantum circuits on IBMQ real hardware to calculate the fidelity of all qubits individually?
Is it possible to get the statevector while running quantum circuits on IBMQ real hardware? If getting the statevector is not possible can I still calculate the fidelity of a qubit somehow?. What I ...
- 33
0
votes
0
answers
210
views
IBM Quantum Lab - Server unavailable or unreachable. Would you like to restart?
In the following circuit, I want to perform tomography on the qubits 0,1,2,3 after qubits 4,5,6,7,8,9 are measured.
I run the circuit using with measurement gates on qubits 4,5,6,7,8,9 with the ...
- 127
1
vote
2
answers
334
views
How to deterministically add two integers on a quantum computer
I am new to the Quantum Computer world. I understand the basics of Quantum mechanics and I have watched a few lectures on Quantum computers, Quantum gates and played a bit on IBM QC.
As far as I ...
1
vote
2
answers
674
views
which device had the best Average coherence time?
These are the IBM backend overview, do: Avg.T1/T2: here stand for the Average decoherence time or coherence time?
- 85
3
votes
1
answer
583
views
How can I know the number of qubits used in a job in qiskit?
How can I know the number of qubits used in a job in qiskit?
I can always do something like
...
- 641
0
votes
1
answer
110
views
Hadamard on first qubit for two qubit state doesn't output what it should on Qiskit
I'm using python qiskit==0.36.2.
The following code:
...
3
votes
1
answer
718
views
How can I write if conditions on quantum registers using qiskit
There is a quantum register measured to state $\left|00\right> $ How can i write a code to check weather the first qubit in measured state is 1 or zero and if 1 do some operations or if 0 do other ...
- 51
2
votes
2
answers
328
views
QV circuits fail to execute in real devices
I tried to change a little the code here for running the quantum volume circuits in real devices. My code is
...
- 641
1
vote
1
answer
1k
views
Can someone explain to me what is T gate and tdg like im five?
I'm newbie to quantum computing, i read about these two gates on IBM quantum computing docs, but I can't seem to understand what is t-gate and tdg or t-dagger, can someone give me a simple explanation ...
- 193
3
votes
1
answer
722
views
How to estimate Qiskit circuit runtime before sending to run on IBM real quantum device?
Qiskit, I tried to estimate circuit runtime using gate_length from Backend.properties()
but its accuracy is very low (real system is 3.5 seconds, estimation is 0.00002 seconds).
So, are there other ...
3
votes
1
answer
380
views
Performance metrics in QSVM
I have implemented QSVM on breast cancer dataset using link: "https://qiskit.org/documentation/stable/0.24/tutorials/machine_learning/01_qsvm_classification.html" but unable to compute other ...
- 317
1
vote
1
answer
299
views
Converting data into a SHA256 hash using Qiskit quantum computer
I was wondering how can we convert data into a hash using Qiskit quantum computer? e.g, this code below will generate a SHA256 hash based on random data.
...
- 193
0
votes
0
answers
78
views
Is there a way to connect a IBM quantum lab code to an Unreal Engine project?
I would like to know whether someone tried this before, I'm interested in be able to connect this tools. I know that Unreal Engine has a plugin to program with python, that all I know. I'll really ...
0
votes
1
answer
89
views
What is $j$ in the state $|\psi\rangle=\sqrt{(1-p)}|0\rangle + e^{j\phi}\sqrt{p}|1\rangle$?
What is the j in the single qubit state equation in the Quantum Phase section? https://quantum-computing.ibm.com/composer/docs/iqx/guide/introducing-qubit-phase it's not defined in the page itself (...
- 103
2
votes
2
answers
383
views
Can I Convert a Qubit in complex form to polar form?
Let's say I have a qubit
$$\left| \psi \right> = (\alpha_1 + i\alpha_2 ) \left|0\right> + (\beta_1 + i\beta_2 )\left|1\right>$$
Can I able convert this to polar form
$$|\psi \rangle = \cos\...
- 55
7
votes
3
answers
3k
views
How are IBM's 127 qubits more potent than the 5760 qubits D-Wave - Advantage_system6.1?
Hi I'm a newbie in quantum computing recently I had a look at the AWS braket and I've seen they had a machine called D-Wave - Advantage_system6.1 that has 5760 qubits but when I googled the highest ...
- 193
1
vote
1
answer
134
views
IBM Q jobs being cancelled without error or explanation?
While sometimes the jobs run without any problem, and in other cases there are errors that can tell how to troubleshoot, in this case it seems there is no explanation from IBM.
Has anyone had similar ...
- 595
2
votes
1
answer
147
views
Iterative quantum phase estimation - real device
I'm trying to implement the iterative quantum phase estimation on a real (IBM) quantum computer. I'm using the code below. When I run this code on a simulator the results are the expected ones, but ...
3
votes
3
answers
528
views
Understanding the output of a Deutsch-Jozsa circuit
I'm looking at the Deustch-Jozsa algorithm. While reading this Qiskit tutorial. I didn't understand what the presented result in plot mean. That is, why the output 1111 means a balanced function? What ...
- 219
1
vote
1
answer
65
views
Qiskit library.gaussian() does not accept parametric expression
I'm trying to build a gaussian pulse in qiskit where I keep the amplitude as a parameter but for the followig code
...
- 11
1
vote
1
answer
399
views
Generating a random 32-byte hex integer using Qiskit
Hello I posted here yesterday about generating random 16 digits using Qiskit, and a gentle guy helped me but how about a string? How can I generate random 256 bit key in hex format in a superposition ...
- 193
1
vote
2
answers
189
views
How do I use the quantum searching algorithm to loop search through a datafile in qiskit?
I have a localhost index.html has a table contains names and address and balances etc... also there is a search bar on the home page to go through the pages, the interesting thing is, there is loooot ...
- 193
3
votes
1
answer
420
views
Question about mock backends!
I recently learned about the mock backends or the fake backends provided by Qiskit and I was wondering, do they behave the same way IBMQ systems backends like (ibmq_brooklyn)? also, can I depend on ...
- 193
2
votes
1
answer
683
views
How does a quantum computer find the correct password faster than classical computers using brute-force?
I didn't get this part right! For example, we have an online box with a 16-digit password, and we don't know what the password is! How can a quantum computer find the correct password faster than ...
- 193
3
votes
2
answers
260
views
IBM Quantum Experiment CNOT
I have a beginner question regarding CNOT-Gates on IBM Quantum.
Assuming the following simple circuit:
...
- 151
0
votes
1
answer
658
views
How to run Quantum Instance into ibmq_qasm_simulator
I have tried to run Shor's algorithm using IBM high performance simulator. I
am currently using QuantumInstance to factorize a number. The code is provided below:
<...
- 43
1
vote
1
answer
230
views
Circuit Construction using IBM Quantum Composer
I am trying to create the following circuit in IBM Quantum Composer but I cannot add the last H gate correctly. It falls in the wrong place. Why?
- 289
1
vote
1
answer
114
views
Design Digital logic circuit in IBM quantum lab
This is my first question here.
I've started doing research in quantum computing. In Digital Logic circuits, there are many circuits (like parity generator, checker, demux etc.) that can be ...
- 25
-1
votes
1
answer
112
views
Quantum ripple-carry adder construction
I am attempting to build a 2-bit ripple-carry adder, using IBM Quantum Experience composer, but I'm confused on how to construct the carry transpose that is shown at the bottom?
- 213
1
vote
0
answers
31
views
What is the relation between the database made up of N elements and the index made up of a string length n in the query model?
I am working on a circuit model that contains a blackbox (query) and do not understand the relationship between what is in the black box and the way we get out the value of the element we index. The ...
1
vote
1
answer
621
views
How to access a qiskit runtime job and query time_taken?
I am trying to execute qiskit runtime jobs on simulators and real machines and I would like to extract information about the time taken to execute each runtime job. Since using python ...
- 85
0
votes
1
answer
1k
views
Decompose native gates using Qiskit framework [closed]
I've read the papers about quantum hardware. These papers [1] [2] mention that native gates of IBM quantum computer are $R_x(\pi/2), R_z(\lambda)\space and \space CR \space (Cross Resonance)$
My ...
- 111
2
votes
1
answer
156
views
Is pennylane free?
I was going through the basics of pennylane. I am able to understand that it is used for quantum neural networks. I am not sure whether it is using paid cloud computer or simulator of xandu or ibmq? ...
- 513
2
votes
1
answer
48
views
Qubit State (theta,phi) Dependence on the Readout Error
Do the readout errors on the publicly available IBM quantum computers have any dependency on the state being measured? That is, if we are measuring a qubit in the state
$\cos({\theta/2}) |0> + e^{i\...
- 65
2
votes
1
answer
355
views
Why does application of Hadamard gate on $|0\rangle$ inverts the state on bloch sphere?
I am trying to understand what is the affect of Hadamard gate on qubit. So far, I understand that applying $H$ gate on qubit, puts the qubit into superposition state where the probability of the qubit ...
- 21
2
votes
2
answers
734
views
Duration of single qubit gate in IBM
how can we calculate the duration of single qubit gate using Qiskit in IBM? In other words if I have to insert a delay in the place of the single qubit gate, how would I know how much delay in ...
- 311
3
votes
1
answer
113
views
What's the difference between depth and num_tensor_factor in qiskit
Now I'm studying about the quantum circuit in qiskit developed by IBM.
The quantum circuit have a several method in itself like depth() and num_tensor_factor().
I don't know what is different between ...
0
votes
1
answer
60
views
Unable to interpret output by qiskit
I have built a simple 2 qubit entanglement circuit and wanted to measure using a real quantum device. I ran the below command an dthe have an output that is not what I was expecting.
qiskit.providers....
- 303
0
votes
0
answers
415
views
Maximum depth of a circuit in IBM
Given Quantum Volume and number of qubits of a IBMQ device, what is the formula to calculate the maximum depth of the circuit that gives high fidelity?
For example: Let us consider ...
- 311
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 ...
1
vote
1
answer
115
views
Results are missing for Qiskit runtime program 'sample-expval'
I have ran some circuits using the code for sample-expval, found in the qiskit docs
While the jobs finished (they appear in my IBM account), when I retrieve some ...
- 123
2
votes
0
answers
235
views
Calculating the Inner Product using Quantum Phase Estimation
I'm following the method laid out in https://arxiv.org/abs/2011.03429 (Page 23 Equations 13-23) to calculate the inner product of two amplitude embedded vectors using Quantum Phase Estimation. I'm ...
- 63
3
votes
1
answer
1k
views
How can I get IBM's API token?
I need an API token to use IBM's real hardware(greater than 5 qubits) in Qiskit, where can I find the price?
- 31
1
vote
0
answers
58
views
Sequential Circuits in IBMQ and Qiskit and generating a clock pulse
I am trying to implement the Peres Gate with Feedback from Feynmann Gate feeding back into the third input to Peres Gate. This sequence needs to be repeated. There is also a clock pulse that needs to ...
- 111