Photonic anti-counterfeiting using structural colors derived from magnetic-responsive photonic crystals with double photonic bandgap heterostructures

Abstract

Herein, based on the recently developed magnetic-induced self-assembly techniques, we designed a novel, simple and low-cost method to fabricate a special class of photonic crystals with double photonic band-gap hetero-structures, and eventually achieved the purpose of modulating the optical diffraction color of the structural colors. The method greatly simplifies the fabrication of photonic crystals with multiple photonic band-gap hetero-structures and extends the modulation means of the optical diffraction color of structural colors. Furthermore, it is worth noting that due to the resulting structural colors that are derived from the double photonic band-gap hetero-structures consisting of double diffraction peaks and presenting a magnetic switching effect through the application and withdrawal of the magnetic fields (0.05 T), which is more difficult to be imitated by those of chemical dyes and pigments, a kind of novel photonic anti-counterfeiting label has been prepared with these structural colors. Due to the widespread counterfeiting of various commercial objects and the urgent requirements of forgery protection, the photonic anti-counterfeiting label demonstrated in our work will undoubtedly find applications in meeting the growing anticounterfeiting needs.

Lithographically Encrypted Inverse Opals for Anti-Counterfeiting Applications

“…For example, colloidal crystals with narrow bandwidth and high transparency can be stacked to form multiple layers, which provide complex optical codes . In addition, colloidal crystals are further patterned to possess identification shapes . Such colloidal crystals delivering combinatorial codes of optical signals and graphical shapes can potentially serve as novel security materials for anti‐counterfeiting of banknotes and passports …”

The comparative study of bulk magneto-phonon and magnetic polaritons of lateral antiferromagnetic superlattices for potential THz applications

“…Compared with complicated two-and three-dimensional photonic crystals [7][8][9][10], the tunable one-dimensional photonic crystals via external stimuli without changing any constituents are readily available and widely used [11][12][13][14]. Since the idea of a lateral superlattice was originally suggested by Wang and Tilley [15], investigations on the topic of lateral magnetic superlattice have become increasingly attractive [15][16][17][18][19][20].…”

Multiple‐response anti‐counterfeiting realized in CaYAl3O7 host with the dual coexistence of Eu2+/Eu3+

“…Information security is an ever-growing global issue with fake banknotes, signatures, documents and goods jeopardizing on the interests of individuals and countries. [1][2][3] Thus, the development of advanced anti-counterfeiting strategies has drawn increasing attention in recent years, where magnetic response, 4,5 plasmonic security labels, 6 and luminescence printing 7 technologies have been explored. Among these, luminescence printing offers advantages of easy handling, high-throughput, and facile design, and is thus the most widely applied against counterfeiting.…”