Partial Measurement of a quantum system

Is there a way to introduce projective measurement in a circuit.

Answer 1

[UDAYA PEDDIRAJU]

Hi John,

the following snippet shows how to do projective measurements.

% Create a quantum circuit with two qubits
circuit = quantumCircuit(2);

quantumCircuit requires MATLAB Support Package for Quantum Computing.

% Apply a Hadamard gate to qubit 1
circuit = hGate(circuit, 1);

% Perform a CNOT operation controlled by qubit 1 on qubit 2
circuit = cxGate(circuit, 1, 2);

% Perform a projective measurement on qubit 2
result = measure(circuit, 2);

% Access the measurement result (either 0 or 1)
measured_state = result.Result;

% Access the probability of obtaining the measured state
probability = result.Probability;

% Display the results
disp(['Measured state of qubit 2: ', num2str(measured_state)]);
disp(['Probability of measured state: ', num2str(probability)]);

you can refer qc toolbox: https://www.mathworks.com/products/quantum-computing.html

Answer 2

[Quantum Computing]

Hi John,

There is code on the File Exchange for computing expectation values that can be used for projective measurements:

Quantum Expectation Values - File Exchange - MATLAB Central (mathworks.com)