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Light control in photonic systems and an improved robustness to imperfections or disorder is in high demand. Recently it has been shown that by breaking time reversal symmetry in photonic systems, it is possible to realize topologically protected states which are resistant to perturbations and back-scattering. This effort has resulted in an increased interest in a new class of topologically ordered optical systems - photonic topological insulators. Some of the approaches to realize topologically protected photonic states include using metamaterials exhibiting a magneto-optical/nonlinear responses, engineering photonic crystal dispersion, as well as introducing synthetic magnetic field for photons. Precise control of topologically protected states can potentially open new frontiers of light matter interaction and lead to a number of applications, such as topologically protected memory/logic devices, compact optical isolators, unidirectional waveguide systems and numerous quantum communication applications. Recent investigations reveal transparent conduction oxides (TCOs) (such as Indium-tin-oxide (ITO) and Al-doped ZnO (AZO)) as a promising building block for on-chip photonics and planar optics applications with ultrahigh modulation capabilities (< 1 [ps]). Within this work we have demonstrated that by integrating a TCO material platform with a standard CMOS-compatible SOI technology, it is possible to get unparalleled ultrafast optical/electrical control of synthetic gauge magnetic field. We have considered a silicon resonator array (510-nm-wide and 220-nm-height) on silicon dioxide integrated with AZO as a dynamically tunable element. It was demonstrated that transitions between topologically protected and non-protected states can be achieved by electrical/optical tuning of 50-nm AZO film.
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