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IBM fake backend vs real backend

Fake backends from qiskit-IBM-runtime package contains calibration results from a snapshot that is hardcoded in the source code. To get a more realistic simulation results, you can use qiskit-aer with ...
Junye Huang's user avatar
0 votes
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Quantum Computing - via Qiskit - error 403

Try logging in to IBMQ account on the webpage. If you are able to do this, copy the API token shown in the top right. Then make use of the code mentioned in this answer,this is the updated code for ...
Yet another Random Guy's user avatar
0 votes

How to suppress long parameters list that appears in the initialize gate?

If your aim is to make a quantum circuit plot that doesn't have this big chunk of initialization state, you can make use of decompose function by qiskit. ...
Yet another Random Guy's user avatar
0 votes

Quantum Computing - via Qiskit - error 403

First got to this website and see if you can login here, this is the latest IBM Quantum website. Once you are able to login you will be able to get your API. Also if you were only using a free plan ...
Shravan Patel's user avatar
5 votes

Are Quantum Computers Bad at Addition?

Yes, current quantum computers are bad at addition. A 5-bit adder requires several dozen two-qubit gates. Current state of the art two-qubit gate error rates are between 0.1% and 1%. At the time I am ...
Craig Gidney's user avatar
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1 vote

Density Matrix for a Quantum Circuit with Clifford Gates and a $T$ Gate in Qiskit

Maybe you can use approximate or Simplified Models Stabilizer Rank Methods: For circuits that predominantly contain Clifford gates and a small number of T gates, you can use techniques based on the ...
Bram's user avatar
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1 vote
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Qiskit: Sum of Kraus operators are not equal to identity matrix

Since OP never disclosed their solution let me shed light on what the mistake here was: the process matrix used as input was a Pauli transfer matrix (i.e. representation matrix in the Pauli basis) but ...
Frederik vom Ende's user avatar
0 votes

Qiskit spends a lot of time on method acquire of thread.lock objects

instead of from qiskit.primitives import Estimator use from qiskit_aer.primitives import Estimator. See https://qiskit.slack.com/...
melechchaim's user avatar
0 votes

Using GPUs with Statevector Simulator in Qiskit 1.0

The qiskit-aer-gpu module depends on cuTensorNet. cuTensorNet supports GPU architectures of Volta, Ampere, and Hopper, which are all sm70 or higher. Since you have ...
Erik Kjellgren's user avatar
5 votes
Accepted

What does Qiskit AerSimulator(memory=True) do?

The parameter memory is used to record and return the measurement outcomes for each shot of the simulation. When you set ...
MonteNero's user avatar
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4 votes

Where to find the Grover's algorithm for Qiskit 1.0.2?

Grover's algorithm is now part of a separate package qiskit-algorithms that must be installed separately. The documentation for the latest version is here, and here are some examples.
Egretta.Thula's user avatar
1 vote
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Simulating Large Quantum Systems with Single T-Gate in Qiskit: Memory Error Beyond Certain Qubit Threshold

On IBM Quantum platform, a universal simulator is limited by 32 qubits. There is also 64-qubit simulator Clifford+T which could be suitable for your problem. You can also run your circuit on 127-qubit ...
Martin Vesely's user avatar
0 votes

Is there a way to use a fake backend for ibm_brisbane?

You can simply import from qiskit_ibm_runtime.fakeprov as following: ...
Guangliang's user avatar
4 votes
Accepted

Why do the same circult yields very different results from different IBM backends?

The problem is caused by a different type of noise each QPU suffers from. Nowadays, it is even not easy to produce two completely same qubits, not to mention two identical QPUs. Please, have a look at ...
Martin Vesely's user avatar
0 votes

Full result of qiskit sampler

The get_counts() function of qiskit return a python dict so I guess the measurement results that are not measured and have for value 0 are not included to save ...
baptistechev's user avatar
1 vote

How to calculate the expected value of a quantum operator in Qiskit (after deprecations)

The expectation value can be calculated in a straightforward way using Statevector.expectation_value like this: ...
Nick Mertes's user avatar
2 votes

How to generate the Bell state $\frac{1}{\sqrt{2}}(|01\rangle+|10\rangle)$ from the state $|00\rangle$ using Qiskit?

The Bell state $\frac{1}{\sqrt{2}}(|01\rangle + |10\rangle)$ can be generated from $|00\rangle$ in Qiskit as follows: ...
Nick Mertes's user avatar
2 votes

How to generate the Bell state $\frac{1}{\sqrt{2}}(|01\rangle+|10\rangle)$ from the state $|00\rangle$ using Qiskit?

Qiskit uses little-endian ordering for both classical bits and qubits. So, the least significant bit (LSB) is the rightmost bit in the binary representation of numbers. That means, you should use <...
Egretta.Thula's user avatar
1 vote

How to create custom fake backend?

One option is to create a new class that inherits from GenericBackendV2 and accepts "noise settings". The below code shows how to do that ...
Egretta.Thula's user avatar
0 votes

How to remove or change the Coupling-Map limit is qiskit?

You can try dropping the backend argument from your transpile() call and that might remove the limitation. The backend argument is used to tell the qiskit ...
Shravan Patel's user avatar
1 vote

How to add noise like depolarising errors in Qiskit SDK 1.0?

You can add measurement error, reset errors, depolarizing error, etc. by making a custom noise model by using the NoiseModel() function from the ...
Shravan Patel's user avatar
1 vote

How to create custom fake backend?

For setting T1/T2 times, measurement error, and other errors (like reset errors etc.) you can make a custom noise model by using the NoiseModel() function from the <...
Shravan Patel's user avatar
0 votes

How to create a qudit of any dimension $d$ in qiskit?

Qiskit has some support for qudits via the dims parameter in Statevector as described here https://docs.quantum.ibm.com/api/...
Nick Mertes's user avatar
3 votes

How can I get the state of my quantum circuit like save_statevector() in qiskit 1.0.2?

Aer is not gone, the namespace integration into qiskit where you could import it ...
Steve Wood's user avatar
  • 1,463
0 votes

How can I get the state of my quantum circuit like save_statevector() in qiskit 1.0.2?

You can use from qiskit.providers.fake_provider import GenericBackendV2, for example (I have slightly changed your code) ...
Roy Elkabetz's user avatar
1 vote

How to create a qudit of any dimension $d$ in qiskit?

In order to do that on a real hardware you will need to create your own discriminator for classifying higher energy states. An old example can be found in here for the case of qutrits (d=3). However, ...
Roy Elkabetz's user avatar
0 votes

How to get properties of real IBM Quantum Computer in Qiskit SDK 1.0?

Once you have got the list of backends from a service as in your load_IBMQ function above (also see get-backend-information in qiskit docs), you can access the ...
Roy Elkabetz's user avatar
3 votes

What goes above this code fragment?

Here's the full code First make sure you have all libraries installed, like qiskit, matplotlib, pylatexenc ...
Yet another Random Guy's user avatar
3 votes

What goes above this code fragment?

First, it holds $TT=T^2=S$. Then we have gate $S$ and its transpose conjugate $S^\dagger$ next to each other. These gates are inverse of each other (because the gates are unitary matrices), so we have ...
Martin Vesely's user avatar
0 votes
Accepted

How to run PegasosQSVC in quantum backend or simulator?

ComputeUncomputecomposes the circuit with its inverse() and this ends up not conforming to the ISA requirement. There is an issue in Qiskit Algorithms specifically ...
Steve Wood's user avatar
  • 1,463
1 vote

Use quantum feauture map different from ZZFeatureMap

RawFeatureVector is not built into a circuit until it's passed parameters. The FidelityQuantumKernel uses a Fidelity which tries ...
Steve Wood's user avatar
  • 1,463
1 vote

How to Properly Run a Circuit with Qiskit on AWS Braket, AttributeError: 'AwsDevice' object has no attribute 'configuration' by Current Implementation

AWSBraketProvider is deprecated, and should be replaced by BraketProvider. After following fagd's answer and using BraketProvider, I am able to submit my jobs.
Chien Kai Ma's user avatar
1 vote
Accepted

How do I get the unitary matrix of a circuit?

You can get back the matrix by using the save_unitary() method on the circuit after creating your circuit. Here is an example : ...
Lena's user avatar
  • 2,597
4 votes
Accepted

Quantum Circuit evaluation Qiskit vs. AWS Braket SDK

The reason for the difference is that Qiskit and Braket use different endianness for their qubits; Qiskit is little endian: $$ | q_{n - 1} \ldots q_2 q_1 q_0 \rangle $$ while Braket is big-endian: $$ |...
Cody Wang's user avatar
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