Week 1: Electrons scattering in a 3D nanowire

Electrons scattering in a 3D nanowire (Datta Ch. 4 and App. B)

Both contacts inject electrons, each according to its own Fermi function: the voltage V only makes the source fill states (μ₁ = μ₀ + qV/2) that the drain leaves empty (μ₂ = μ₀ − qV/2). Electrons fly in straight lines. At random moments they collide and leave in a random 3D direction (orange flash). Bounces off the side walls are mirror reflections, not collisions. Drag the picture to rotate it.

● injected by the source ● injected by the drain ○ collision (trails show where each electron has been)

Wire length L Mean free flight vτ Voltage V Animation speed

Crossed the whole wire0 / 0

Datta's λ = (4/3) vτ–

Theory T = λ/(λ+L)–

Flights shorter than vτ–

Source → drain crossings0

Drain → source crossings0

Net = current0

I = (q²/h)·T·V, one mode–