Understanding Quantum Teleportation

Introduction

In this post we'll delve into the fascinating realm of Quantum Computing with a focus on a topic that sounds straight out of a science fiction movie - Quantum Teleportation. Despite its fantastical name, Quantum Teleportation is real and it's an essential component of many Quantum Computing applications including quantum key distribution (QKD).

Quantum Teleportation

Quantum Teleportation involves transferring the quantum state of a particle - an atom, ion, or photon - from one location to another, without any physical transportation of the particle itself. This process, predicated on the principles of Quantum Mechanics, enables us to transmit quantum information across vast distances.

Here's a simple illustration of Quantum Teleportation using the Qiskit framework, which is an open-source quantum computing library for Python.

Quantum Teleportation with Qiskit

First, let's install Qiskit. In Python:

!pip install qiskit

Now let's define a function for quantum teleportation.

from qiskit import QuantumCircuit, transpile, assemble, Aer, execute
from qiskit.visualization import plot_histogram, plot_bloch_multivector

def quantum_teleportation(circuit, qbit1, qbit2, qbit3):

    # Step 1: The qubit to be sent is position 0, we start by applying the gates:
    circuit.h(qbit2)
    circuit.cx(qbit2, qbit3)

    # Step 2: Apply the CNOT gate on qbits 1 and 2, then an H-gate to qbit 1:
    circuit.cx(qbit1, qbit2)
    circuit.h(qbit1)

    # Step 3: Measure qbits 1 and 2:
    circuit.measure([1,2], [0,1])

    # Step 4: Apply controlled gates after measurement:
    circuit.cx(qbit2, qbit3)
    circuit.cz(qbit1, qbit3)
    return circuit

In this function a Quantum Circuit is created for three qubits with two classical bits. An H-gate (Hadamard gate) is applied to create superposition. Then measurements are applied to the first two qubits. Depending on the results, an X-gate (CNOT gate) and a Z-gate (Pauli-Z gate) are applied to the third qubit.

And that's it! With this simple function, we can simulate quantum teleportation right on our machine. This shows how far we've come in the field of Quantum Computing, leveraging principles from Quantum Mechanics to solve complex problems in ways we could have never imagined a few years ago.

Conclusion

From this simple example, we can see how Quantum Teleportation underpins the emerging field of Quantum Computing. The journey we've embarked on is just beginning and there's a lot more promising developments that Quantum Computing holds for our future. Stay with us for more exciting topics on Quantum Computing in our upcoming blogs.