This paper explores the potential of non-Hermitian lattice systems to enhance Hamiltonian parameter estimation in quantum sensing. While the non-Hermitian skin effect doesn't offer a distinct advantage, other effects lead to dramatic improvements. Specific asymmetric non-Hermitian tight-binding models with Z₂ symmetry demonstrate an exponential increase in quantum Fisher information per photon with system size. This advantage persists even with non-Markovian and non-perturbative effects, making it compatible with various quantum optical and superconducting circuit platforms.

Alexander McDonald, Aashish A. Clerk