Geometric Phase of Exceptional Point as Quantum Resonance

This paper investigates the geometric phase associated with encircling an exceptional point (EP) in a scattering model, bridging non-Hermitian spectral theory and quantum resonances. It uses the complex scaling method to analyze the behavior of eigenstates near an EP, providing insights into the self-orthogonality and Berry phase in this context. The work is significant because it connects abstract mathematical concepts (EPs) to physical phenomena (quantum resonances) in a concrete scattering model.