Squeezed Light — Homodyne Detection

Squeezed states of light reduce quantum noise below the shot-noise limit in one quadrature (X̂) at the cost of amplified noise in the conjugate (P̂). The Wigner function W(x,p) is a quasi-probability distribution visualising the quantum state.

Squeezing r 0.8 Phase φ 0.00 Displacement α 1.0

W(x,p) = (2/π) exp[−2(σₓ(x−x₀)² + σₚ(p−p₀)²)] | σₓ=e^{−r}, σₚ=e^{r}