Wave Packet Revival

Quantum wave packet spreading, collapse, and fractional revival in an infinite square well

Packet Parameters

Potential

Spread: —

Display

Revival Physics

In infinite well: Eₙ = n²·E₁
ψ(x,t) = Σₙ cₙ φₙ(x) e^{-iEₙt/ℏ}

Revival time:
T_rev = 2πℏ/(E₁·α)
where α = d²E/dn² × n₀

At t = T_rev/p: p fractional revivals appear — ghost copies of original packet.

1/2 revival: two half-packets
1/3 revival: three copies

Discovered in Rydberg atoms (1990s). Applications in quantum control.