QuantumSim

QuantumSim is a simulator for quantum computing.

Cloning and checking

Clone the repository

git clone https://github.com/CaffeineMakesCode/QuantumSim

Run the checks from the root folder

cd <path-to-repository>/QuantumSim && make check

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Usage

The QubitLayer class in src/QubitLayer.cpp defines the functions for the quantum gates and the arrays that store the amplitudes for the qubits. The table below lists the functions that can be used by a QubitLayer object. precision is a typedef for double.

Quantum Gate	Function
Pauli X	pauliX(int target)
Pauli Y	pauliY(int target)
Pauli Z	pauliZ(int target)
Hadamard	hadamard(int target)
Rotation X	rx(int target, precision theta)
Rotation Y	ry(int target, precision theta)
Rotation Z	rz(int target, precision theta)
Controlled NOT	cnot(int control, int target)
Toffoli	toffoli(int control1, int control2, int target)
Multiple controlled CNOT	mcnot(int *controls, int numControls, int target)
Controlled Phase	cphase(int control, int target)
Multiple controlled Phase	mcphase(int *controls, int numControls, int target)

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Example

Running a quantum circuit is done by writing the circuit in src/main.cpp.

#include <iostream>
#include <complex>
#include "QubitLayer.hpp"
#include "qAlgorithms.hpp"

int main(){
    // create a QubitLayer object
    QubitLayer q;
    // apply a hadamard gate
    q.hadamard(0);
    // apply cnot on the 2 qubits
    q.cnot(0, 1);
    // print qubits
    q.printQubits();
}

This circuit creates an EPR pair.

By default when a QubitLayer object is created, it is initialised with 2 qubits. To setup a larger quantum circuit, a QubitLayer object can be constructed using arguments.

#include <iostream>
#include <complex>
#include "QubitLayer.hpp"
#include "qAlgorithms.hpp"

int main(){
    // create a QubitLayer object with 4 qubits
    QubitLayer q(4);
    // apply hadamard gates
    q.hadamard(0);
    q.hadamard(2);
    // apply cnot gates
    q.cnot(0, 1);
    q.cnot(2, 3);
    // print qubits
    q.printQubits();
}

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Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.

Please make sure to update tests as appropriate.