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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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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Cirq/OpenFermion Trotterization of parametrised FermionOperator?
I am using OpenFermion and Cirq. I would like to define a Hamiltonian with a symbolic parameter and then generate a quantum circuit via Trotterization of its time evolution, which then also contains ...
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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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Amplitude Amplification applied to HHL Algorithm
I’m trying to understand and implement the amplitude amplification algorithm described in the HHL paper. I’m using the cirq implementation of the HHL algorithm as my starting point.
I have a couple of ...
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AttributeError: module 'cirq' has no attribute 'google'
I have just installed Qiskit, Qutip, and Cirq in my Anaconda Enviornment. When I tried to run the test program:
...
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Simulating density matrices in quantum simulators
I would like to load random quantum states sampled from a given density matrix based on its classical probabilities ie based on the definition of the given density matrix: $\rho = \sum_i p_i |\psi _i \...
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Cirq : Reference for Toffoli decomposition
I was trying to find a reference for the 7 T-gate decomposition of the Toffoli gate given by Cirq. The decomposition originates from the the one used for CCZPowGate as given in the doc string here
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How can I define two distinct sets of qubits? (Cirq)
I am trying to familiarise myself with Cirq, and I came across something I don't know how to code.
I would like to define two sets of qubits as follows: say the number of qubits in set 1 and 2 are ...
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