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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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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Need help regarding building a custom VQE
I want to write code for a custom Variational Quantum Eigensolver (VQE) capable of computing eigenvalue(s) for non-Hermitian systems, based on this paper. I have formulated a cost function (provided ...
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Initialize circuit by density matrix (i.e. mixed state) by Cirq, Qiskit, QuTip
I want to do a simulation involving:
mid-circuit measurement (i.e. based on the measurement result of some qubits to append further gates on other qubits; e.g., Pauli error correction in entanglement ...
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Variational Quantum Eigensolver (VQE) by scipy minimize in cirq does not work
I tried to make a cirq program calculating an eigenvalue of the observable by VQE. Inspired by the qulacs VQE tutorial, I defined a cost function from the expectation value of the observable with ...
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How to create a 3-D state (array) of qubits in qiskit or cirq etc?
I want a 3-D cube-like array for state of qubits, on which I want further to implement different sets of rotations, etc, for cryptographic means. You can create a 2D grid qubit in cirq with ...
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Tensorflow_quantum hybrid models tf-quantum
I am trying to QCNN for MNIST classification equivalent to that built in.
I’m having problems trying to pass my quantum circuit built with cirq as a Keras layer. Here’s what I have:
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If Statement OpenQasm 2.0
in the documentation for OpenQasm 2.0 it says one can use an if statement like so:
if(c_reg==int) Quantum Operation.
However, I would like to execute the following: ...
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How to best implement this algorithm?
I am trying to design an algorithm to find a solution to a certain problem. I have N qubits which encode the problem (let's call them the problem qubits) and one check_qubit (which is flipped to |1>...
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Controlled NOT gate which flips target when at least one of the control qubits is |1>
I would like to have a controlled NOT gate which flips my target qubit when at least one of the control qubits is |1>.
I would like to be able to do this for arbitrary n. For a system with 2 ...
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Classical control of an entire sub-circuit in cirq
I would like to evolve a quantum state through an entire sub-circuit in my circuit based on classical control. I am aware of the current state of classical control in cirq (https://quantumai.google/...
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Is there a way to find the computational resources required to perform a simulation of n- qubits in Cirq similar to qsim?
I’m trying to model basic spin chains in 1D using VQE (ideal circuit) with cirq and qsim. The models have between 10-20 sites and varying interactions (nearest neighbour, next to nearest neighbour etc)...
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How to Find a circuit that evolves from one density matrix to another(qiskit or cirq)
given two density matrices, dmBefore and dmAfter, I want to generate(find) a circuit in Qiskit or Cirq that starting initaliazed with dmBefore ends with dmAfter after it's execution. Is it possible?.
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Cirq seems to output 0 instead of |2> with qutrits
I am experimenting a bit with qutrits on Cirq and came across a problem: my output is 0 when it should be |2>.
I defined my qutrit as follows:
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AttributeError: module 'cirq_google' has no attribute 'Foxtail'
I have installed cirq in my anaconda environment by using the command:
pip install cirq
When I ran the code below to print the ...
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How to create a multicontrol mcx gate or operation in cirq
In qiskit the method to apply a multi control with more than 2 control qubits is:
qc.mct ( listcontrols,targetbit,listancillas, mode=mode[i])
What is the ...
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Grover's algorithm for max cut problem - Implementation in cirq
I am using the Grover's algorithm for max cut problem using an oracle for the graph described below to check whether it admits a valid 2-coloring.
Here are the edges: (0,3),(0,4),(1,3),(1,4),(2,3),(2,...
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Marking a specific quantum state in the oracle function in the Grover's algorithm
I have a simple implementation of Grover's algorithm. As depicted in the results below, the oracle function marks the state |111>. How can I change the Oracle function to mark |010>?
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Understanding the meaning of [2, 2] for input_register and target_register in a custom Cirq gate
I'm learning a custom gate implementation from google Cirq official tutorial of shor algorithm(https://colab.research.google.com/github/quantumlib/Cirq/blob/master/docs/experiments/shor.ipynb#scrollTo=...
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Resolving AWS-Braket - ValidationException: An error occurred (ValidationException) when calling the CreateQuantumTask operation
I have a quantum circuit for the Markovian Reservoir Engineering[MRE] Model, written in cirq (frontend) and trying to run it on Ionq hardware, using qbraid credits. This is all being done on qbraid ...
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Custom noise models in Cirq
I want to simulate a quantum circuit using Cirq, with a noise model that defines a certain error rate $e_1$ for single-qubit gates and a certain error rate $e_2$ for 2-qubit gates.
So I know it's ...
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tensorflow, tensorflow-quantum, tensorflow-federated latest version compatibility?
I have been working with on some research on tensorflow, tensorflow-quantum and tensorflow-federated and the problem with that is I just can't install those three at my google colab and I tried ...
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Generalizing a brick-wall circuit acting on qubits to acting on qudits
Recently, I have been creating a "brick layer" circuit of random unitary gates (each acting on 2 qubits) which acts on a n qubit register using cirq. A typical circuit looks like this.
(...
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Two-time correlators in Cirq?
Is there a way to calculate two-time correlators in Cirq directly? For example, suppose we have an initial mixed state described by a density matrix $\rho_0$, and we want to obtain in our quantum ...
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Efficient simulation of circuit with variable depth using Cirq
I have a program that needs to evaluate several Cirq circuits by using both simulators the Simulator() and ...
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How to take gradient of the `tfq.layers.State` output?
I am using the following code for building a quantum circuit as a custom tf.keras.layers.Layer:
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How to change the qubits of a cirq Circuit?
I am constructing generic circuits, and I would like to change the qubits after creating the circuits. Is there a way in cirq to do so?
for instance:
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Topmost Universal Gate Based Quantum Simulator?
I am Elijah I'm interested in Drug Discovery and Materials Simulation. I want to purchase a gate based Quantum Simulator for research. I received a proposal.
Full State Simulator 30 Qubits on Laptop, ...
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how to flatten a cirq.Circuit with CircuitOperation
I have a cirq.Circuit that uses a CircuitOperation, something like:
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How can i describe Custome Gate Sets in Cirq?
i try to create a Custome GateSet with the CompilationTargetGateset class but it does not work.
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Is there a method in pyQuil to create logical boolean gates
is there another way to represent a boolean gate. The straight forward way would be to define a gate my a matrix and then apply this gate to the circuit. What i mean by that? For Example an AND-Gate ...
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Convert an integer to its basis state in Cirq
I am trying to implement Quantum Adder using QFT in Cirq. I previously did the same problem using Pennylane, in which I converted an integer into its Basis state using the BasisStatePreparation method ...
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How to rewrite this Cirq problem into Qiskit?
I have a following example problem in Cirq, representing a very simple operator given by
$$
\hat{H} = a^\dagger_0a_2 + a_0a^\dagger_1 + 0.9\, a^\dagger_0a_1a^\dagger_2a^\dagger_3 + a^\...
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Merge two Y**0.5 gate into a single Y gate
How can I merge two consecutive cirq.Y**0.5 gates into a single cirq.Y gate with a transformer?
I can use ...
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Two Qudit custom gate error in Cirq
I am trying to build two qudit CX (d-dim) gate.
and getting below error.
There is no issue in the unitary matrix.
Please suggest to resolve the error.
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Interpretation of Qudit measurement output in cirq
Here [+1] represents X gate for qutrit. How the Counter value is coming to 5? which is the measurement outcome(q0q1q2->102). Even for (q0q1q2->101) also counter value is 5.
In total, for this 3 ...
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How we can perform measurements on an X, Y or Z basis in cirq?
How we can perform measurements on an X, Y or Z basis in cirq? Is there any function where we can give the list of qubits and measurement basis as an argument and get the output?
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Printing Stabilizer State of a circuit using Cirq
How to print the stabilizers for a given circuit using Cirq (just like in Qiskit)?
For example, if I have the following cluster state and make a circuit using Cirq. I give the circuit as input, and I ...
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Why importing cirq_ionq gives an unexpected argument error
I'm trying to install cirq_ionq, a python library for running cirq circuits on IonQ's quantum hardware. However, when I try importing it I get an unexpected argument error:
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is cirq suitable for simulation of quantum error correction?
I experimented with stim and qiskit for QECC simulations. They both have limitations : for example stim has no support for non-clifford operations (qiskit does); qiskit has no support for multiple ...
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$S^2$ expectation value of a circuit seems wrong
I need to rewrite a following circuit from Cirq to Qiskit with $2\varphi = \pi$.
It's a circuit representing an initial state for VQE calculation. Considering, that ...
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CIRQ How to iteratively apply a multi qubit gate to first n qubits
I've got an arbitrary n qubit circuit, with a "for Q in range(n):", which creates a custom gate class that affects (Q+1) qubits, which I want to apply to first (Q+1) qubits of the circuit ...
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Use simulator.simulate() to obtain probability distribution instead of simulator.run() (cirq)
So far, I have my code set up to find the probability distribution using simulator.run(), and I was wondering if I can use the simulator.simulate() function instead to obtain a probability ...
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How to measure a qubit and depending on measurement outcome act with a gate (cirq)
Is there a way on cirq that I can make a measurement on a qubit, and depending on the outcome of that measurement act with another gate on that qubit. So, I want to measure a qubit (in the ...
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Circuit gives unexpected phase factor (cirq)
I implemented the following circuit on cirq:
For clarity: the circuit consists of X gates, (controlled) Hadamard gates (H), N-toffoli gates, and reset operations (R).
The (1,4) qubit is the one I ...
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duality quantum computing simulation
I am a starter of this quantum mostly new to quantum computing but I wonder if there is any option of simulating duality quantum computing in qiskit or IBM q or any other alternative way?
Duality ...
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In Cirq, how do I separate transpilation from execution in simulator.simulate()?
In Qiskit, there are explicit transpile (where a circuit is transpiled to primitive gates) and backend.run (where the circuit is executed in either statevector simulation or real hardware) steps. What ...
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Question about Controlled Modulo Quantum Gate
How does the Ux(x, N) function implements Ux|y> -> |xy mod N> ?
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