講演情報
[9p-N221-5]Numerical simulation of skin effect in a non-Hermitian photonic crystal
〇ThanhHuyen Phan1, Katsunori Wakabayashi1 (1.Kwansei Gakuin Univ.)
キーワード：
photonic crystals、non-Hermition photonics、skin effect
The topological states in Hermitian systems have been identified via the property of the band inversion and experimentally realized in serval photonic crystal systems. On the other hand, studies of non-Hermitian systems have pointed out the non-Hermitian skin effects, which are theoretically proved to be protected by non-trivial winding of complex eigenfrequencies in complex plane and are unique without Hermitian counterpart. Therefore, skin effects promise to make the gain and loss in systems become controllable. To experimentally realize non-Hermitian skin effects, theoretical calculations and simulations are required.In this work, we focus on numerical generation of skin effects in a two-dimensional non-Hermitian photonic crystal system. Our photonic crystal consist of one dielectric block in one unit cell, whose dielectric constant is n=2-i as shown in Fig. 1(a). Figure 1(b) is its photonic. band structure. The non-trivial point gap is numerically observed in the complex plane at several k-points. At the real normalized frequency 0.52 as shown in Fig. 1(c), there are two corresponding imaginary part, which indicates the different damping rate at the same frequency. Field distribution of a bulk mode and a skin mode of a finite structure are shown in Fig. 1(d). We will numerically generate electromagnetic waves in a finite structure to observe skin effect. Our results support for the experimental realization of skin effects.