Non-Hermitian systems are physical systems whose effective Hamiltonians or dynamical generators are not equal to their Hermitian conjugates, leading to complex eigenvalues and non-orthogonal eigenstates. They naturally model open, dissipative, or gain–loss systems where energy or probability is not conserved, such as in photonics, acoustics, and cold-atom platforms. Non-Hermitian systems exhibit distinctive phenomena including exceptional points, non-Hermitian skin effects, and modified bulk–boundary correspondence, often described using biorthogonal bases. They are analyzed via non-Hermitian extensions of quantum and wave theories, with particular attention to spectral properties, stability, and the role of symmetries such as parity–time (PT) symmetry.
A research team led by Professor Shuichi Hiraoka at the University of Tokyo and Professor Masanori Tachikawa at Yokohama City University has quantitatively analyzed how molecules pass through dynamic nanoscale pores using ...
Nanomaterials
Jun 3, 2026
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Quantum geometry describes quantum states in systems with changing system parameters, such as an electron spinning in a magnetic field whose direction is slowly changing. The state of the electron evolves, and this change ...
Optics & Photonics
May 6, 2026
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Three RIKEN researchers have demonstrated a way to stop problematic "dark modes" from squelching intriguing effects in quantum systems. This advance could help with the development of more versatile quantum devices that can ...
Optics & Photonics
Apr 24, 2026
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A stable "exceptional fermionic superfluid," a new quantum phase that intrinsically hosts singularities known as exceptional points, has been discovered by researchers at the Institute of Science Tokyo.
General Physics
Dec 29, 2025
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132
The convergence of non-Hermitian physics and topological photonics has opened exciting research directions in recent years, particularly in the development of robust laser systems.
Optics & Photonics
Dec 13, 2025
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Exceptional points (EPs) are non-Hermitian singularities where two or more eigenstates coalesce, resulting in the eigenspace collapsing in dimensionality. Over the past decade, researchers have uncovered a wealth of exotic ...
Optics & Photonics
Nov 26, 2025
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A research team has observed multibody interaction-induced EPs and hysteresis trajectories in cold Rydberg atomic gases. They revealed the phenomenon of charge-conjugation parity (CP) symmetry breaking in non-Hermitian multibody ...
General Physics
Jun 11, 2025
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Exceptional points (EPs) are unique types of energy-level degeneracies that occur in non-Hermitian systems. Since their existence was first proposed more than a century ago, physicists have only been able to experimentally ...
A research team led by The Hong Kong University of Science and Technology (HKUST) has achieved a groundbreaking quantum simulation of the non-Hermitian skin effect in two dimensions using ultracold fermions, marking a significant ...
Condensed Matter
Jan 8, 2025
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The spectral degeneracies emerging as a consequence of parity-time (PT) symmetry exhibit a profound divergence from their conventional counterparts. They possess non-Hermitian nature and are designated as exceptional points ...
Optics & Photonics
Sep 12, 2024
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