Lithium Niobate Photonic Topological Insulator-based Multi-Wavelength Optical Demultiplexer with Piezoelectric Switch-Off

Abstract

Photonic topological insulators provide unidirectional, robust, wavelength-selective transport of light at an interface while keeping it insulated at the bulk of the material. The non-trivial topology results in an immunity to backscattering, sharp turns, and fabrication defects. This work leverages these unique properties to design a 2-channel optical demultiplexer based on a lithium niobate photonic topological insulator with piezoelectric switch-off capabilities. A photonic topological insulator design for the demultiplexer allows for good wavelength selectivity, crosstalk as low as $-$54 dB, and better isolation between output channels. The primary operating wavelengths presented are the telecommunication wavelengths of 1310 nm and 1550 nm, but the use of the lithium niobate material allows operation at multiple operating wavelengths. Furthermore, we propose a post-fabrication method to switch off the topological protection and, thus, optical transmittance via an applied voltage utilizing the inverse piezoelectric effect of lithium niobate. This work will contribute to advancing lithium niobate integrated photonics and developing efficient, multi-wavelength, electrically controlled optical communication systems and integrated photonic circuits.

added reference to journal

References in corpus (20)

• Topological Insulators
• Quantum Spin Hall Effect in Graphene
• Topological Insulators with Inversion Symmetry
• Topological Photonics
• Topological Photonics
• Photonic Floquet Topological Insulators
• Possible Realization of Directional Optical Waveguides in Photonic Crystals with Broken Time-Reversal Symmetry
• Topological Crystalline Insulators
• Photonic Analogue of Two-dimensional Topological Insulators and Helical One-Way Edge Transport in Bi-Anisotropic Metamaterials
• Colloquium: Topological Band Theory
• Integrated photonics on thin-film lithium niobate
• Inverse design and demonstration of a compact and broadband on-chip wavelength demultiplexer
• All-Si Valley-Hall Photonic Topological Insulator
• Observation of Photonic Topological Valley-Hall Edge States
• Photonic Topological Insulator in Synthetic Dimensions
• Realization of a three-dimensional photonic topological insulator
• Band topology in classical waves: Wilson-loop approach to topological numbers and fragile topology
• Tutorial: Computing topological invariants in two-dimensional photonic crystals
• Photonic topological insulators a beginner's introduction
• Probing rotated Weyl physics on nonlinear lithium niobate-on-insulator chips