942 citations · 1.1k across the 9 of their papers we have counts for
9 papers
Realization of Non-Hermitian Hopf Bundle Matter
Yung Kim, Hee Chul Park, Minwook Kyung +6
Line excitations in topological phases are a subject of particular interest because their mutual linking structures encode robust topological information of matter. It has been rec…
Comment on "Amplified emission and lasing in photonic time crystals"
Jagang Park, Hee Chul Park, Kyungmin Lee +5
Lyubarov et al. (Research Articles, 22 July 2022, p. 425) claim that the spontaneous emission rate of an atom vanishes at the momentum gap edges of photonic Floquet media. We show…
Non-Hermitian chiral degeneracy of gated graphene metasurfaces
Soojeong Baek, Sang Hyun Park, Donghak Oh +9
Non-Hermitian degeneracies, also known as exceptional points (EPs), have been the focus of much attention due to their singular eigenvalue surface structure. Nevertheless, as perta…
Revealing non-Hermitian band structures of photonic Floquet media
Jagang Park, Hyukjoon Cho, Seojoo Lee +7
Periodically driven systems, characterised by their inherent non-equilibrium dynamics, are ubiquitously found in both classical and quantum regimes. In the field of photonics, thes…
Resonance-enhanced spectral funneling in Fabry-Perot resonators with a temporal boundary mirror
Kanghee Lee, Junho Park, Seojoo Lee +4
A temporal boundary refers to a specific time at which the properties of an optical medium are abruptly changed. When light interacts with the temporal boundary, its spectral conte…
Observation of an exceptional point in a non-Hermitian metasurface
Sang Hyun Park, Sung-Gyu Lee, Taewoo Ha +6
Exceptional points, also known as non-Hermitian degeneracies, have been observed in parity-time symmetric metasurfaces as the parity-time symmetry breaking point. However, the pari…
Linear frequency conversion via sudden merging of resonances in time-variant metasurfaces
Kanghee Lee, Jaehyeon Son, Jagang Park +4
Energy conversion in a physical system requires time-translation invariance breaking according to Noether's theorem. Closely associated with this symmetry-conservation relation, th…
Low-dimensional optical chirality in complex potentials
Sunkyu Yu, Hyun Sung Park, Xianji Piao +2
Chirality is a universal feature in nature, as observed in fermion interactions and DNA helicity. Much attention has been given to chiral interactions of light, not only regarding…
Switching teraherz waves with gate-controlled active graphene metamaterials
Seung Hoon Lee, Muhan Choi, Teun-Teun Kim +9
The extraordinary electronic properties of graphene, such as its continuously gate-variable ambipolar field effect and the resulting steep change in resistivity, provided the main…