What's New
The quantum category now has six fully playable simulations covering the core ideas of quantum information science. You can explore them individually or work through them in order as a self-guided introduction to quantum computing.
No prior quantum knowledge needed. Each simulation includes a plain-language explanation of the underlying physics, the key equations in a math box, and an interactive sandbox to build intuition before diving into the theory.
The Six Simulations
Qubit & Bloch Sphere
Drag the qubit state vector around the Bloch sphere. Watch how gates (H, X, Y, Z, S, T) rotate it — visualising superposition and phase in real time.
Quantum Circuit Builder
Drag-and-drop quantum gates onto a multi-qubit register. The state vector updates live — watch amplitudes evolve through CNOT, Hadamard, and Toffoli gates.
Quantum Entanglement
Create Bell states and perform simulated measurements. Observe the correlation between entangled qubits and verify the CHSH inequality violation.
Quantum Spin Precession
Spin-½ particle precessing in a magnetic field — Larmor precession, Rabi oscillations, and the rotating wave approximation all in one interactive demo.
Quantum Tunneling
A wave packet impinging on a rectangular potential barrier. Watch it split into transmitted and reflected parts — adjust barrier height and width to control transmission probability.
Grover's Search Algorithm
The O(√N) quantum search algorithm visualised step by step. Watch amplitude amplification concentrate probability on the target state across √N oracle calls.
Suggested Learning Order
If you're new to quantum computing, work through the simulations in this order. Each one builds on the previous:
- Qubit & Bloch Sphere — understand a single qubit as a state vector
- Quantum Spin Precession — see where the Bloch sphere comes from physically
- Quantum Tunneling — wave-particle duality and the Schrödinger equation
- Quantum Entanglement — two-qubit states and Bell measurement correlations
- Quantum Circuit Builder — compose multi-qubit gates into algorithms
- Grover's Algorithm — the first exhibit of genuine quantum advantage
For a deeper dive into the physics and algorithms behind these simulations, see our Spotlight #13: Quantum Computing post.