$\mathcal{P}\mathcal{T}$-symmetry breaking in a necklace of coupled optical waveguides

I V Barashenkov, L Baker, N V Alexeeva

We consider parity-time ($\mathcal{P}\mathcal{T}$) symmetric arrays formed by $N$ optical waveguides with gain and $N$ waveguides with loss. When the gain-loss coefficient exceeds a critical…