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Title: Isotropic topological second-order spatial differentiator operating in transmission mode

Differentiation has widespread applications, particularly in image processing for edge detection. Significant advances have been made in using nanophotonic structures and metamaterials to perform such operations. In particular, a recent work demonstrated a topological differentiator in which the transfer function exhibited a topological charge, making the differentiation operation robust to variations in operating conditions. The demonstrated topological differentiator, however, operates in reflection mode at off-normal incidence and is difficult to integrate into compact imaging systems. In this work, we design a topological differentiator that operates isotropically in transmission mode at normal incidence. The device exhibits an optical transfer function with a symmetry-protected topological charge of±<#comment/>2and performs second-order differentiation. Our work points to the potential of harnessing topological concepts for optical computing applications.

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Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Letters
0146-9592; OPLEDP
Page Range / eLocation ID:
Article No. 3247
Medium: X
Sponsoring Org:
National Science Foundation
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