New answers tagged qiskit
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Is there a way to perform Zero Noise Extrapolation with qiskit without using the runtime service?
There are several other ways to implement ZNE besides directly using Qiskit Runtime - there are various libraries and functions that allow you to program ZNE more directly. I recommend Mitiq - this ...
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Is there a way to perform Zero Noise Extrapolation with qiskit without using the runtime service?
qiskit.primitives Estimator is a reference statevector based implementation. It has no noise (other than it can simulate variance for shot/sampling noise) so it has no such capability.
There is an ...
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Frequency of qubits in qiskit simulators
The qubit frequency is not encoded into the noise model. You can however attach noise to the delay gate. See here.
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Netlist of the transpiled circuit in Qiskit
It very much depends on what do you mean by a netlist.
If you are searching for a human-readable serialization format of a non-dynamic circuit, I would recommend you OpenQASM 2
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Modifying measurements in a Qiskit circuit
Since the last answer, now there is an easier solution:
Get an ordered dictionary of the operators in circuit and check if ...
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Simulator able to run SwitchCase in qiskit?
The latest version of Qiskit Aer (version 0.13) supports SwitchCaseOp. So, if it's OK to run your circuit locally, you can use Aer simulators:
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Conditioned gates with multiple classical bits
You can use bit_xor function from the newly added classical expressions module
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Conditioned gates with multiple classical bits
This can be done quite easily. For instance, take the case where you have two classical bits $c_1, c_2$ and would like to implement $X^{c_1+c_2}$ on a qubit $q$. Clearly, applying $X^{c_1}$ followed ...
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Mapping a QUBO onto an observable for use with Qiskit QAOA
First of all, you will need to convert your problem into a QuadraticProgram
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If_test() - Dynamic Circuits in qiskit
It appears there's a misunderstanding regarding the use of if_test and _else constructs in your code. In Qiskit, these ...
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Why doesn´t Grover's Algorithm work for my Qiskit circuit?
For Grover algorithm to work, the initial state must be a uniform superposition of all the states. Since your initial state is different, Grover algorithm will not work. Instead, you should use its ...
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How is a linear combination of pauli operators applied to a quantum circuit in qiskit?
The operation $\frac{1}{\sqrt{2}}[X - Z]$ is unitary. You can easily check that:
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How to measure in $\sigma_x$ basis in Qiskit?
It's a bit long for a comment but my goal is to explain that the answer linked as duplicate does indeed answer your question.
The measure operation of qiskit ...
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QISKIT: ValueError: too many subscripts in einsum DensityMatrix()
Try to transpile your circuit into 1- and 2-qubit gates:
qc = transpile(qc, basis_gates=['cx', 'u'])
rho = DensityMatrix(qc)
This issue happens because Numpy ...
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What does U mean in pulse schedules for superconducting quantum computers?
You're already answering your own question: U0 stands for the control channel on qubit 0, as you can read in Table 1 of https://iopscience.iop.org/article/10.1088/...
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Does qiskit_ionq have the possibility of simulating quantum circuits with noise?
You can use a noise_model backend option to use a noisy simulator:
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How to fix two flip-bit errors in a 3 qubit input
I was able to figure it out now via taking 3 ancilla qubits instead of 2 and figuring out the invariant in case 2 bits are flipped.
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Inverse Quantum Fourier Transformation
So I found out, that the Rz gate didn't do what I thought it did. I found another a way to represent the controlled phase gate with single qubit gates and CNOT over this Link https://physics....
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Phase shift on qiskit quantum teleportation simulation
Qiskit uses little-endian bit ordering (see this answer for details). It seems that you didn't take that into consideration in some places in your code.
For example, to tensor product ...
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Get parameters of a CU gate for implementing an erroneous CX gate with fidelity = 0.81
tl;dr: The operation you're describing is not unitary and cannot be implemented with a CU gate.
A standard CX gate implements the operation
$$
CX = |0\rangle\langle 0| \otimes \mathbb{1} + |1\rangle\...
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I have two Choi matrix I suspect be equivalent. Can I manipulate them?
There is a one-to-one relation between Choi states$^1$ and quantum channels (Choi-Jamiołkowski isomorphism). So, you cannot transform the Choi matrix without changing the channel it represents. If the ...
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Is Qiskit's Estimator Primitive running PauliStrings in Parallel?
The Runtime Estimator you used groups Paulis into commuting groups that can be measured simultaneously which is why you are seeing that result since the operator you have the paulis will group ...
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Using "extern" functions in OpenQASM3
It is not possible for external users to define their own extern functions currently for IBM hardware.
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Quantum error correction circuit from stabilizer codes
You have not specified what $j$ is in your question.
The section before the first vertical dotted line is the encoding circuit.
You can use the stabilizer formalism to see that this encoding circuit ...
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