Wave Packet Spreading
Free-particle dispersion ω=ħk²/2m: group velocity v_g = 2×phase velocity. Peaks march at v_p; envelope races at v_g.
σ₀ (nm)
σ₀ = 1.0 nm
k₀ (nm⁻¹)
k₀ = 5.0 nm⁻¹
Time
t = 0 fs
Animation
⏸ Pause
t =
0
fs
σ(t) =
1.000
nm
v_g =
0
nm/fs
v_p = v_g/2 =
0
nm/fs
⟨x⟩ =
0
nm