Questions tagged [noise]
For questions about different types of noise a quantum computer (or qubits) may experience; how this affects the outcome of the computation; how to reduce a specific type of noise on a specific implementation of quantum computer; or how to simulate noise.
228 questions
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Comparing the Erasure and Depolarizing Noise Channels in QEC
Are there any quantum error-correction codes which have been found to exhibit high thresholds for either Pauli-based depolarizing noise or Erasure noise channels, but not for both? Are there reasons ...
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What is the Stim color_code:memory_xyz circuit executing?
In Stim's color_code:memory_xyz, the all data qubits are first initialized to the |0> state, then the Z-type stabilizer measurement circuit is executed, and ...
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How can I extract actual Pauli error in Stim?
I am using a quantum circuit simulator "Stim" to simulate the logical error probability of color code under circuit-level noise.
In the code capacity noise and the phenomenological noise, ...
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Propagation rules for the cross-resonance gate of IBM ($R_{zx}$)
The $R_{zx}$ is the fundamental two-qubit gate supported by IBM processors. I'd like to see how Pauli operators propagate over such a gate.
Other well-known cases are shown in the picture below.
- 2,058
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Error Model on id gate, is not giving any error
I am trying to play with NoiseModel of qiskit, and I noticed that error on id gate is not giving any error results, while error ...
- 1,502
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How to differientate the noise functions in qiskit?
In Qiskit, there are many different Quantum Error Functions.
From my understanding, pauli_error represents the error rate of $X, Y, Z$ independently, and ...
- 1,423
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436
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unexpected effect of coherent unitary error in qiskit
I'm trying to simulate the effect of a coherent unitary Z rotation at an arbitrary angle of a single qubit on the fidelity of a quantum circuit. I am using the qiskit Aer noisy simulator. More ...
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How can I implement a kraus_error in qiskit?
I have successfully run bit_flip_error in Qiskit by function pauli_error, but I can not find how to implement a ...
- 585
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before_round_data_depolarization in Stim surface code circuits
I am working with Stim to do some circuit-level noise simulations and I have a doubt on the noise model and the stim implementation. I can generate stim circuits for the surface code using the ...
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Error Mitigation in Dynamic Quantum Circuits: Alternatives to Dynamical Decoupling?
"I have a regular quantum circuit (i.e., not a dynamic one), let's call it qc. When I run it on a real quantum computer without using dynamical decoupling, the result is poor. However, when I ...
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Is it sufficient to assume a constant coherent error?
I've recently started working with quantum errors and noise and came across an intriguing but simple question. When we consider coherent errors in quantum gate operations, it's common to model them as ...
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Manualy setting 'id' operation error probability in GenericBackendV2 doesn't work
I am trying to alter the noise probability for 'id' operation in GenericBackendV2. This is my code:
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How can I find out how compatible a quantum circuit is to a backend without executing the circuit
Say I have multiple backends, I need a score to determine how well a backend is suitable for that particular circuit, I have it's noise model too, I tried transpiling the circuit and calculating noise ...
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210
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Qiskit Noisy simulator sample code or documentation
I have to run some quantum circuits on Noisy simulator of qiskit? I tried searching some noisy simulator of qiskit but could not find anything. It would be great if someone can direct me to a qiskit ...
- 513
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Error on expectation value even with zero noise
If I use V2 fake backends, I can set a certain noise equal to 0 with
backend.target['measure'][(0,)].error = 0
and I can do that for each kind of instruction ('id',...
- 513
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Impact of various kinds of noise on calculation of operator's expectation value
I am trying to calculate the expectation value of an operator Op on Qiskit's simulator with noise present. I am trying to study the impact of various kinds of ...
- 199
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How can I perform syndrome measurements for both X-type and Z-type stabilizers in Stim?
I would like to simulate the logical error rate of the surface code under depolarizing noise using Stim. The decoder I am using decodes from both X-type and Z-type stabilizer syndrome values. ...
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How can I determine if the error correction by estimated error results in a logical error in circuit-level noise?
I am trying to simulate the logical error probability of color code under circuit-level noise.
In the code capacity noise and the phenomenological noise, the Pauli errors to the data qubits that occur ...
- 81
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Adding controllable noise to VQE to find ground state energy
I am wanting to add noise to my code which uses VQE to find ground state energy for LiH at various inter atomic distances. The code I am wanting to add to is the code found from the qiskit text book. ...
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Does anybody know what a low-degree Markov field is?
In the paper Fast Estimation of Sparse Quantum Noise I saw the following description:
quantum devices approaching the fault-tolerant regime will have very
few significant errors (and therefore are ...
- 669
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212
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Adding Calibration Data For Noise Model
I am building a custom noise model using Qiskit's NoiseModel class. I want to incorporate full range of calibration data, say for 7 qubit machine. I am not sure how to incorporate calibration features ...
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Is it possible to find a cNOT implementation that preserves a biased $X$ noise
I am interested in qubits which are biased in noise. For my purpose I assume that I have only bit-flip (i.e. Pauli $X$) noise in my algorithm.
In the presence of such noise, quantum gates can convert ...
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Paper on geometry of 2-level Quantum states influenced by noise
Are there papers discussing geometry of quantum states (especially two level systems) influenced by noise.
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How can I implement a circuit that simulates white noise on $n$ qubits?
I want to test an error model of the convex form
$$t \times \text{ideal_state} + (1-t)\times \text{noisy_circuit}.$$
In terms of density matrices, this would look like
$$t\rho_{\text{idealState}}+(1-t)...
- 331
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Error parameters from Qiskit backends
In order to build a custom noise model in Qiskit Aer, I requested the error parameters from different backends and got 3 (9) parameters for each single-qubit (two-qubit) gate as output. However, I ...
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How to introduce error to the stim circuit exported from Crumble
I am not successful to add a noise model to the circuit that I created in Crumble and transferred into STIM with stim.Circuit(''' .... '''), without adding them by hand.
I see the examples of stim....
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Building a DIY quantum computer - how to reduce a noise?
I refer to A DIY Guide to Building a Quantum Computer and Researchers advance noise cancelling for quantum computers.
With my friends, I would like to build our simplified quantum computer.
We are ...
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Error when tryng to import quantum aer noise
I have been trying to implement noise reducer in aer simulator in my code. This is the line of code for import:
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