Open AccessObservation of Weyl exceptional rings in thermal diffusion
Author(s) -
Guoqiang Xu,
Wei Li,
Xue Zhou,
Huagen Li,
Ying Li,
Shanhui Fan,
Shuang Zhang,
Demetrios N. Christodoulides,
ChengWei Qiu
Publication year - 2022
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.2110018119
Subject(s) - dissipative system , diffusion , hermitian matrix , physics , thermal , coupling (piping) , topology (electrical circuits) , theoretical physics , mathematics , quantum mechanics , materials science , thermodynamics , combinatorics , metallurgy
Significance Thermal diffusion is dissipative and strongly related to non-Hermitian physics. At the same time, non-Hermitian Weyl systems have spurred tremendous interest across photonics and acoustics. This correlation has been long ignored and hence shed little light upon the question of whether the Weyl exceptional ring (WER) in thermal diffusion could exist. Intuitively, thermal diffusion provides no real parameter dimensions, thus prohibiting a topological nature and WER. This work breaks this perception by imitating synthetic dimensions via two spatiotemporal advection pairs. The WER is achieved in thermal diffusive systems. Both surface-like and bulk states are demonstrated by coupling two WERs with opposite topological charges. These findings extend topological notions to diffusions and motivate investigation of non-Hermitian diffusive and dissipative control.