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Newest 'cirq' Questions - Quantum Computing Stack Exchange
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Learn more about TeamsQuestions tagged [cirq]
A python framework for creating, editing, and invoking Noisy Intermediate Scale Quantum (NISQ) circuits. It is a Python library for writing, manipulating, and optimizing quantum circuits and running them against quantum computers and simulators.
187 questions
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1
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0
answers
46
views
Performing a Partial Trace on Arbitrary Subsystems with Python/QuTiP/Cirq
I have a composite quantum system with density matrix rho represented as a NumPy array of shape $(D,D)$, where $D = \prod_i d_i$ is the product of the dimensions of ...
0
votes
1
answer
64
views
Which endianess convention is used by Cirq?
I know that Qiskit uses the little-endian convention for qubit ordering and statevector indexing, while Pennylane uses the big-endian convention. Which convention is used by Cirq?
0
votes
0
answers
30
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What is the meaning of the exponent_neg and exponent_pos parameters in PauliStringPhasorGate in Cirq?
The PauliStringPhasorGate gate in Cirq takes as input a Pauli string, which is exponentiated. I do not understand why two parameters can be given: exponent_neg and exponent_pos?
To make my question ...
2
votes
1
answer
181
views
How can a beginner start contributing to quantum open-source projects (e.g., Qiskit/Cirq)?
I’m new to quantum computing and eager to contribute to open-source projects like Qiskit or Cirq. Could you recommend:
Beginner-friendly resources (tutorials, books, or courses) to build foundational ...
2
votes
1
answer
144
views
Converting stim circuit into cirq and back with Detectors?
I am attempting to work in both stim and cirq and was testing moving back and forth between the two and got an error for a ...
3
votes
1
answer
154
views
Help me in understanding the State Change After the Final CNOT Gate in this Quantum Circuit
I am a beginner in the quantum computing field and have recently taken Qiskit 101, where I first created my quantum circuit.
What I was focusing on was understanding the change in state at each gate. ...
2
votes
0
answers
130
views
Is there a theoretical method to achieve a positive semi-definite density matrix in QST?
The problem of encountering negative eigenvalues in the density matrix during Quantum State Tomography (QST) is well-explained in this Quantum Computing Stack Exchange post.
However, I am seeking ...
0
votes
0
answers
57
views
How can I measure qutrits in the X basis using cirq?
I attempted to create a custom measurement class which, in my case, allows us to go from the z basis to x basis using a hadamard gate transformation, and then we measure wrt that new basis. However, ...
1
vote
1
answer
174
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quantum multiplier for large numbers
I am working on a project where I need to calculate 3x+1 for numbers 0 to infinity. I have an 8GB RAM laptop and I am using Cirq. For small numbers, I was able to perform the multiplication using the ...
0
votes
0
answers
83
views
Why does cirq produce a non-positive semidefinite density matrix doing quantum tomography?
While doing quantum tomography in cirq, I ended up getting a density matrix which is not positive semi-definite. Why is this so? Here's the code I used:
...
-1
votes
2
answers
132
views
How to do quantum tomography on a subsystem of 2 of 30 qubits in cirq?
I have a 30 qubit system and I need to do quantum tomography on a subsystem of 2 of its qubit. How can I do this in Cirq?
1
vote
0
answers
66
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Finding partial trace in CIRQ
Suppose I have a 30 qbit system, due to computational complexity, I can't find the density matrix of the system. But is it possible to find the partial trace of the a sub-system of 2 qubits out of 30 ...
3
votes
2
answers
455
views
How to compose a larger circuit onto a smaller circuit in Qiskit, adding extra quantum registers to some fixed list
$\newcommand{\ket}[1]{|{#1}\rangle}$
I have a Qiskit quantum circuit for multiplication $M$, that I want to compose onto another qiskit quantum circuit for inner ...
0
votes
1
answer
256
views
How to implement a depolarizing noise channel for qutrits using cirq?
Anyone have any idea how I can implement a depolarizing noise channel for qutrits using cirq? Say using the kraus operators within a class inheriting from cirq.Gate or so?
2
votes
1
answer
87
views
How does the cirq compilation process work?
Cirq compilation process.
I cannot find the documentation that describes the internal structure of the library Cirq by Google.
There is much information related to high level functions, but none ...
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