Please use this identifier to cite or link to this item:
Title: Topological insulator metamaterial with giant circular photogalvanic effect
Authors: Sun, X.
Adamo, Giorgio
Eginligil, Mustafa
Krishnamoorthy, Harish Natarajan Swaha
Zheludev, Nikolay I.
Soci, Cesare
Keywords: Science::Physics
Issue Date: 2021
Source: Sun, X., Adamo, G., Eginligil, M., Krishnamoorthy, H. N. S., Zheludev, N. I. & Soci, C. (2021). Topological insulator metamaterial with giant circular photogalvanic effect. Science Advances, 7(14), eabe5748-.
Project: MOE2016-T3-1-006 (S)
Journal: Science Advances
Abstract: One of the most notable manifestations of electronic properties of topological insulators is the dependence of the photocurrent direction on the helicity of circularly polarized optical excitation. The helicity-dependent photocurrents, underpinned by spin-momentum locking of surface Dirac electrons, are weak and easily overshadowed by bulk contributions. Here, we show that the chiral response can be enhanced by nanostructuring. The tight confinement of electromagnetic fields in the resonant nanostructure enhances the photoexcitation of spin-polarized surface states of topological insulator Bi1.5Sb0.5Te1.8Se1.2, leading to an 11-fold increase of the circular photogalvanic effect and a previously unobserved photocurrent dichroism (ρcirc = 0.87) at room temperature. The control of spin transport in topological materials by structural design is a previously unrecognized ability of metamaterials that bridges the gap between nanophotonics and spin electronics, providing opportunities for developing polarization-sensitive photodetectors.
ISSN: 2375-2548
DOI: 10.1126/sciadv.abe5748
Rights: © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).
Fulltext Permission: open
Fulltext Availability: With Fulltext
Appears in Collections:SPMS Journal Articles

Files in This Item:
File Description SizeFormat 
8.pdf3.3 MBAdobe PDFView/Open

Page view(s)

Updated on Nov 30, 2021


Updated on Nov 30, 2021

Google ScholarTM




Items in DR-NTU are protected by copyright, with all rights reserved, unless otherwise indicated.