= London screening with an unnormalized complex condensate
{c}
{title2=$\lambda_L^{-2}=2e^2v^2$}
For scalar kinetic term $|D\varphi|^2$ and condensate magnitude $|\varphi|=v$ without a factor $1/\sqrt2$, the canonical vector mass is $m_A^2=2e^2v^2$. In a constant-phase gauge the current is $\mathbf j=-2e^2v^2\mathbf A$. A static magnetic field obeys $\nabla^2\mathbf B=m_A^2\mathbf B$, so its penetration length is $1/(\sqrt2|e|v)$. This normalization differs from defining the vacuum amplitude as $v/\sqrt2$.
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