Optical squeezing degradation by loss
= Optical squeezing degradation by loss
{title2=$V_{\rm out}=\eta V_{\rm in}+(1-\eta)/4$}
Mixing a mode with independent vacuum on a <beam splitter> of <intensity> transmission $\eta$ gives the displayed <optical quadrature> <variance> when vacuum <variance> is $1/4$. It approaches vacuum noise as transmission falls. Phase noise instead mixes squeezed and anti-squeezed axes, and cannot in general be represented by the same efficiency alone.