Questions 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.
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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 ...
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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, ...
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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 ...
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How do I perform measurements in the X basis for qutrits in cirq?
After applying the hadamard gate to a 0 state qutrit, I should be able to get it into the + state, but how do I then measure the circuit in the X basis as opposed to the computational basis?
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Expectation values with finite number of shots with qsimcirq
I was using qsimcirq for VQE to obtain exact expectation values of the energy for a certain Hamiltonian with
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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:
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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?
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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 ...
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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 ...
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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?
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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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How to convert a custom observable matrix to a Cirq observable for simulation?
I aim to conduct a Cirq simulation using a custom observable. However, the measure_observables function in Cirq requires an Iterable of cirq.PauliString, making it challenging to directly use a custom ...
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cirq entanglement qubits
The following code originates from a third-party, although, I have added the commented line containing "UNCOMMENT THE START OF THIS LINE".
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How can we see on Cirq that Google Sycamore has 54 qubits?
Hello, can you explain how to see in Google Cirq that the figure above is a 54 qubits quantum computer ? thanks
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Measuring a specific observable using cirq
I am simulating a circuit in cirq, and I need to measure an observable $$A(\theta) = R^\dagger_z(\theta)XR_z(\theta),$$
and I am not quite sure how to do that.
My first thought was to apply these ...
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