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arXiv · 1805.05209

Non-quantized square-root topological insulators: a realization in photonic Aharonov-Bohm cages

Mark Kremer·Ioannis Petrides·Eric Meyer·Matthias Heinrich·Oded Zilberberg·Alexander Szameit
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Abstract

Topological Insulators are a novel state of matter where spectral bands are characterized by quantized topological invariants. This unique quantized non-local property commonly manifests through exotic bulk phenomena and corresponding robust boundary effects. In our work, we report a new type of topological insulator exhibiting spectral bands with non-quantized topological properties, but with a quantization that arises in a corresponding system where the square of the Hamiltonian is taken. We provide a thorough theoretical analysis as well as an experimental demonstration based on photonic Aharonov-Bohm cages to highlight the bulk and boundary properties of this neophyte state of matter.

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Mark Kremer, Ioannis Petrides, Eric Meyer, Matthias Heinrich, Oded Zilberberg, Alexander Szameit. 2018-05-14. Non-quantized square-root topological insulators: a realization in photonic Aharonov-Bohm cages. https://arxiv.org/abs/1805.05209

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