Quantum metric and wavepackets at exceptional points in non-Hermitian systems

Abstract

The usual concepts of topological physics, such as the Berry curvature, cannot be applied directly to non-Hermitian systems. We show that another object, the quantum metric, which often plays a secondary role in Hermitian systems, becomes a crucial quantity near exceptional points in non-Hermitian systems, where it diverges in a way that fully controls the description of wavepacket trajectories. The quantum metric behaviour is responsible for a constant acceleration with a fixed direction, and for a non-vanishing constant velocity with a controllable direction. Both contributions are independent of the wavepacket size.

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Cited by in corpus (30)

• Experimental measurement of the divergent quantum metric of an exceptional point
• Biorthogonal quantum criticality in non-Hermitian many-body systems
• Extracting the Quantum Geometric Tensor of an Optical Raman Lattice by Bloch State Tomography
• Ground-state quantum geometry in superconductor-quantum dot chains
• Observation of Quantum metric and non-Hermitian Berry curvature in a plasmonic lattice
• Quantum metric of non-Hermitian Su-Schrieffer-Heeger systems
• Quantum-geometry-induced anapole superconductivity
• Quantum geometric effect on Fulde-Ferrell-Larkin-Ovchinnikov superconductivity
• Dynamical scaling of Loschmidt echo in non-Hermitian systems
• Generalized Quantum Geometric Tensor in a Non-Hermitian Exciton-Polariton System
• Topological properties of a non-Hermitian quasi-1D chain with a flat band
• Universal semiclassical equations based on the quantum metric
• Piezoelectric effect and diode effect in anapole and monopole superconductors
• Non-Hermitian topological exciton-polariton corner modes
• Identifying non-Hermitian critical points with quantum metric
• Quantum metric on the Brillouin Zone in correlated electron systems and its relation to topology for Chern insulators
• Pseudospin-orbit coupling and non-Hermitian effects in the Quantum Geometric Tensor of a plasmonic lattice
• Quantum metric dependent anomalous velocity in systems subject to complex electric fields
• Bulk-boundary correspondence in topological systems with the momentum dependent energy shift
• Anisotropic exciton-polaritons reveal non-Hermitian topology in van der Waals materials
• Quantum geometrical effects in non-Hermitian systems
• Direct Measurement of a Non-Hermitian Topological Invariant in a Hybrid Light-Matter System
• Band topology of pseudo-Hermitian phases through tensor Berry connections and quantum metric
• Programmable non-Hermitian photonic quantum walks via dichroic metasurfaces
• Direct measurement of the quantum geometric tensor in pseudo-Hermitian systems
• Minimal Hamiltonian deformations as bulk probes of effective non-Hermiticity in Dirac materials
• Multi-block exceptional points in open quantum systems
• Topological photonics in nanoscaled systems with far field radiation and polarization singularities
• Flat band mediated photon-photon interactions in 2D waveguide QED networks
• Fidelity and quantum geometry approach to Dirac exceptional points in diamond nitrogen-vacancy centers