Optical Lattices with Higher-order Exceptional Points by Non-Hermitian Coupling

Abstract

Exceptional points (EPs) are degeneracies in open wave systems with coalescence of at least two energy levels and their corresponding eigenstates. In higher dimensions, more complex EP physics not found in two-state systems is observed. We consider the emergence and interaction of multiple EPs in a four coupled optical waveguides system by non-Hermitian coupling showing a unique EP formation pattern in a phase diagram. In addition, absolute phase rigidities are computed to show the mixing of the different states in definite parameter regimes. Our results could be potentially important for developing further understanding of EP physics in higher dimensions via generalized paradigm of nonHermitian coupling for a new generation of parity-time (PT) devices.

arXiv commentTo appear: Appl. Phys. Lett

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Cited by in corpus (11)

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• Chiral symmetry in non-Hermitian systems: product rule and Clifford algebra
• Exceptional Degeneracies in Traveling Wave Tubes with Dispersive Slow-Wave Structure Including Space-Charge Effect
• Exceptional points in oligomer chains
• Characterizing and Tuning Exceptional Points Using Newton Polygons
• Generalized Bose-Hubbard Hamiltonians exhibiting a complete non-Hermitian degeneracy
• Generalized Parametric Space, Parity Symmetry of Reflection, and Systematic Design Approach for Parity-Time Symmetric Photonic Systems
• Multitude of exceptional points in van der Waals magnets
• Flux-mediated effective Su-Schrieffer-Heeger model in an impurity decorated diamond chain
• Scalable higher-order exceptional surface with passive resonators
• Exceptional flat bands in bipartite non-Hermitian lattices