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In the past decade, the field of topological photonics has gained prominence exhibiting consequential effects in quantum information science, lasing, and large-scale integrated photonics. Many of these topological systems exhibit protected states, enabling robust travel along their edges without being affected by defects or disorder. Nonetheless, conventional topological structures often lack the flexibility for implementing different topological models and for tunability post fabrication. Here, we present a method to implement magnetic-like Hamiltonians supporting topologically protected edge modes on a general-purpose programmable silicon photonic mesh of interferometers. By reconfiguring the lattice onto a two-dimensional mesh of ring resonators with carefully tuned couplings, we show robust edge state transport even in the presence of manufacturing tolerance defects. We showcase the system’s reconfigurability by demonstrating topological insulator lattices of different sizes and shapes and introduce edge and bulk defects to underscore the robustness of the photonic edge states. Our study paves the way for the implementation of photonic topological insulators on general-purpose programmable photonics platforms.
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Experimental Realization of Multiple Topological Edge States in a 1D Photonic Lattice
Abstract Topological photonic systems offer light transport that is robust against defects and disorder, promising a new generation of chip‐scale photonic devices and facilitating energy‐efficient on‐chip information routing and processing. However, present quasi one dimensional (1D) designs, such as the Su–Schrieffer–Heeger and Rice–Mele models, support only a limited number of nontrivial phases due to restrictions on dispersion band engineering. Here, a flexible topological photonic lattice on a silicon photonic platform is experimentally demonstrated that realizes multiple topologically nontrivial dispersion bands. By suitably setting the couplings between the 1D waveguides, different lattices can exhibit the transition between multiple different topological phases and allow the independent realization of the corresponding edge states. Heterodyne measurements clearly reveal the ultrafast transport dynamics of the edge states in different phases at a femtosecond scale, validating the designed topological features. The study equips topological models with enriched edge dynamics and considerably expands the scope to engineer unique topological features into photonic, acoustic, and atomic systems.
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- Award ID(s):
- 1807552
- PAR ID:
- 10462929
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Laser & Photonics Reviews
- Volume:
- 13
- Issue:
- 2
- ISSN:
- 1863-8880
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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