Dual-Polarization Second-Order Photonic Topological Insulators

Abstract

Second-order photonic topological insulators that host highly localized corner states resilient to defects, are opening new routes towards developing fascinating photonic devices. However, the existing works on second-order photonic topological insulators have mainly focused on either transverse magnetic or transverse electric modes. In this paper, we propose a dual-polarization topological photonic crystal structure for both transverse magnetic and transverse electric modes through topology optimization. Simple tight-binding lattice models are constructed to reveal the topological features of the optimized photonic crystal structure in a transparent way. The optimized dual-polarization second-order photonic topological insulator hosts four groups of corner states with different profiles and eigenfrequencies for both the transverse magnetic and transverse electric modes. Moreover, the robustness of theses corner states against defects is explicitly demonstrated. Our results offer opportunities for developing polarization-independent topological photonic devices.

9 pages, 9 figures

References in corpus (7)

• Scheme to Achieve Silicon Topological Photonics
• Electric Multipole Moments, Topological Multipole Moment Pumping, and Chiral Hinge States in Crystalline Insulators
• Visualization of higher-order topological insulating phases in two-dimensional dielectric photonic crystals
• Direct observation of corner states in second-order topological photonic crystal slabs
• Novel Topological Phase with Zero Berry Curvature
• Photonic crystal nanocavity based on a topological corner state
• Low-threshold topological nanolasers based on second-order corner state

Cited by in corpus (8)

• A brief review of topological photonics in one, two, and three dimensions
• Topological metasurface: From passive toward active and beyond
• Higher-order topological states mediated by long-range coupling in $D_4$-symmetric lattices
• Topologically protected second-harmonic generation via doubly resonant high-order photonic modes
• Topological photonic crystal fibers based on second-order corner modes
• Spin-Polarized Fractional Corner Charges and Their Photonic Realization
• Observation of gapless corner modes in synthetic translation dimensions
• Polarization-independent second-order photonic topological corner states