Biexciton Binding Energy Landscape (2D)

Quantum Dot (2D lateral cross-section)

Dot radius R 3.0 nm

Correlation strength κ 1.00×

Pump rate 1.5

Temperature 77 K

Dot State

empty

Live Readouts

Exciton E_X

— eV

Biexciton E_XX

— eV

Binding energy ΔXX

— meV

Linewidth (FWHM)

— meV

How this 2D version works

Same underlying model as the 3D version, rendered two completely different ways instead of one 3D orbiting-particle scene. A single electron-hole pair (exciton, X) recombines and emits a photon of energy E_X; a second pair fills the s-shell to form a biexciton (XX), decaying XX → X → 0.

E_X(R) = E_g + ħ²π²/(2R²)·(1/m_e* + 1/m_h*) − 1.8e²/(4πεε₀R)
ΔXX(R) ≈ k₁/R − κ·k₂/R²      (2·E_X − E_XX = ΔXX)

The top panel is a true 2D lateral cross-section — carriers doing a confined 2D random walk inside a disk of radius R (a real lateral quantum-dot geometry), not a flattened camera view of a 3D orbit. The middle strip is a binding-energy landscape: ΔXX plotted against R itself, so the entire bound/antibound crossover is visible at once as a curve, with a marker at the live R and shaded bound (green) / antibound (red) regions — a genuinely 2D, graph-native way to see the size-dependent sign flip that the 3D version could only report one point of at a time. The bottom strip is the same kind of live accumulated photoluminescence histogram as the 3D version, computed independently here from the same recombination-event stream.

Dot radius R — sets confinement energy and where R crosses the ΔXX=0 line on the landscape panel.
Correlation strength κ — scales the correlation/exchange term; watch the crossover marker on the landscape slide toward larger R as κ grows (crossover sits exactly at R₀=κ·k₂/k₁).
Pump rate — Poisson-like injection of new electron-hole pairs into the disk.
Temperature — broadens each spectral line's linewidth via phonon dephasing.

Electron Hole