Supermetal-insulator transition in a non-Hermitian network model

We study a non-Hermitian and non-unitary version of the two-dimensional Chalker-Coddington network model with balanced gain loss. This belongs to class D^dagger particle-hole symmetry^dagger hosts both skin effect as well exceptional points. By calculating its two-terminal transmission, we find novel contact induced by effect, which results in non-quantized transmission for chiral edge states. In addition, exhibits an insulator 'supermetal' transition, across changes from exponentially decaying system size growing size. clean system, critical point separating supermetal is characterized Dirac that produces quantized 4, instead value 1 expected Hermitian systems. change consequence When adding disorder exponent divergence localization length \nu \approx 1, same characterizing universality systems D. Our work provides way exploring behavior systems, using models, past proved versatile tools describe physics.