⚛️ Quantum Physics

Double-Slit ExperimentCoherent wave diffraction through a double slit — choose between wave mode (FTCS… Schrödinger EquationPopular1D time-dependent Schrödinger equation solved via split-operator method. Gaussian wave… Hydrogen OrbitalInteractive 3D hydrogen probability densities |ψₙₗₘ|² for quantum numbers n, l, m. Rendered… Quantum TunnellingA Gaussian wave packet scatters off a potential barrier — adjust barrier height and momentum… Quantum Harmonic OscillatorEnergy levels Eₙ = ℏω(n+½) and wavefunctions ψₙ(x) of the quantum harmonic oscillator.… Heisenberg Uncertainty PrinciplePopularLive demonstration of Δx·Δp ≥ ℏ/2 using a Gaussian wave packet displayed simultaneously in… Quantum Spin ChainA classical Heisenberg spin chain of 32 vectors evolves under Landau-Lifshitz dynamics —… Wave Packet InterferenceTwo Gaussian wave packets collide and interfere in a 1-D box (split-operator method). Vary… Quantum Circuit SimulatorPopularClick-to-place quantum circuit builder for up to 3 qubits. Supports H, X, Y, Z, S, T, CNOT,… BB84 Quantum Key DistributionStep through the BB84 protocol: Alice sends qubits in random bases, Bob measures, and they… Quantum Billiard — Particle in a Box & Quantum ChaosExplore quantum billiards: rectangular and stadium-shaped particle-in-a-box, eigenstates,… Quantum Harmonic Oscillator — Wavefunctions & Energy LevelsExplore the quantum harmonic oscillator interactively. Visualize wavefunctions ψ_n(x),… Quantum Wave Packet — Gaussian Wavepacket & Heisenberg UncertaintySimulate a quantum mechanical Gaussian wave packet. Watch Re(ψ), Im(ψ), and |ψ|² evolve in… Quantum TunnellingDrag Energy E/V₀ and barrier width to watch a wave partly tunnel through a rectangular or… Bell's InequalityNewWatch entangled spins violate the CHSH inequality: classical hidden variables cap out at… Grover's AlgorithmNewWatch quantum amplitude amplification find a marked item in O(√N) queries as the oracle… Quantum Walk — Superposition vs Classical DiffusionNewA quantum walker uses a Hadamard coin at each step: unlike classical diffusion (sigma ~… Bose-Einstein Condensate — Emergence of CoherenceNewCool bosons toward absolute zero: below critical temperature Tc, a macroscopic fraction… Stern-Gerlach Experiment — Spin QuantisationNewSend silver atoms through an inhomogeneous magnetic field: classically they should smear… Rabi Oscillations — Driven Two-Level AtomNewDrive a two-level atom with a resonant field: the population oscillates coherently between… Bloch Sphere — Visualising a QubitNewEvery pure qubit state is a point on the Bloch sphere. Apply X, Y, Z, H and phase gates and… Aharonov-Bohm Effect — Phase Without a FieldNewElectrons passing either side of a confined magnetic flux acquire a measurable phase… Casimir Effect — Force From the VacuumNewTwo uncharged parallel plates in a vacuum attract: they exclude long-wavelength vacuum… Quantum Dot Emission — Size-Dependent FluorescenceNewVisualize how quantum dot size controls emission wavelength via the Brus equation. Smaller… 2D Spin Lattice — Heisenberg FerromagnetNewSimulate a 2D spin-1/2 lattice with Metropolis Monte Carlo. Watch spontaneous magnetization… Quantum Harmonic OscillatorEnergy eigenstates and wavefunctions using Hermite polynomials — probability density… De Broglie Matter Waves — λ = h/mvNewExplore de Broglie matter waves: tune mass and velocity to see λ = h/(mv) live, from… Jaynes–Cummings Model — Vacuum Rabi OscillationsNewInteractive Jaynes–Cummings simulator: watch vacuum Rabi oscillations of a single atom… Particle in a Box Simulator — Quantum Energy LevelsNewInteractive particle-in-a-box simulator: visualize quantized energy levels, eigenstate… Feynman Path Integral — Sum Over HistoriesNewExplore Feynman's sum-over-histories: generate random A→B paths, add their phasors… Quantum Decoherence — T1/T2 Qubit Dephasing SimulatorNewWatch a qubit's coherence decay live: tune T2 dephasing and T1 relaxation times and starting… Quantum Eraser Experiment — Which-Path Marker & Restored InterferenceNewInteractive quantum eraser simulation: tag photons with a which-path marker to destroy… Wigner Function Visualiser: Quantum Phase-Space HeatmapNewExplore the Wigner quasi-probability distribution W(x,p) for vacuum, coherent, Fock and…