Quantum teleportation, to be clear, has nothing to do with teleporting physical objects. Instead, it's a fascinating aspect of quantum mechanics which allows us to send quantum information from one place to another, without physically sending the state itself. It's worth understanding how it works, so in this post, I'm going to describe the theoretical concept behind quantum teleportation and then guide you through the steps of simulating it with IBM's Qiskit library.
Remember, a key feature of quantum mechanics is the entanglement of particles. Essentially, if two quantum systems become entangled, the state of one system is directly related to the state of the other, no matter the distance between them. This leads to the concept of teleportation.
At a very high level, in quantum teleportation you have a sender (traditionally called Alice), a receiver (Bob), and an entangled pair of quantum bits (qubits). Alice wants to send one of her qubits to Bob, so she uses one qubit from the entangled pair and sends Bob the result of a measurement - which can be sent over a classical communication channel. Bob can then use this classical information to reconstruct Alice's qubit on his end.
We'll begin by installing Qiskit. You can do this with pip:
pip install qiskit
Afterwards, we'll start by creating a quantum circuit in Qiskit with three qubits: one for Alice, one for the entangled pair that Alice will use, and, one for Bob:
from qiskit import QuantumCircuit # Create a Quantum Circuit with 3 qubits qc = QuantumCircuit(3) # Step 1: Creating Entanglement between second and third qubit qc.h(1) qc.cx(1, 2) print(qc)
Now let's prepare Alice's qubit, that she wants to send to Bob and then perform some operations related to the entangled qubits:
# Step 2: Preparing the quantum state to teleport qc.x(0) qc.barrier() # Step 3: Applying operations related to Alice's qubit and the first part of the entangled pair qc.cx(0, 1) qc.h(0) qc.barrier() print(qc)
Finally, Alice measures her two qubits and sends them to Bob via a classical channel. Based on what he receives, Bob applies certain gates to his qubit from the entangled pair:
# Final Step: Depending on the classical bits received, Bob applies certain gates to reconstruct the initial state. qc.cx(1, 2) qc.cz(0, 2) print(qc)
And that's the basic process of quantum teleportation! The state of Alice's original qubit has been transported to Bob's qubit.
This is just the beginning of what you can do with quantum computing. As the field continues to develop and quantum computers become more widely available, who knows what incredible new applications we'll discover?