Chiral lanthanide lumino-glass for a circularly polarized light security device
Yuichi Kitagawa, Satoshi Wada, M. D. Jahidul Islam, Kenichiro Saita, Masayuki Gon, Koji Fushimi, Kazuo Tanaka, Satoshi Maeda, Yasuchika Hasegawa
Abstract
Abstract Artificial light plays an essential role in information technologies such as optical telecommunications, data storage, security features, and the display of information. Here, we show a chiral lanthanide lumino-glass with extra-large circularly polarized luminescence (CPL) for advanced photonic security device applications. The chiral lanthanide glass is composed of a europium complex with the chiral (+)-3-(trifluoroacetyl)camphor ligand and the achiral glass promoter tris(2,6-dimethoxyphenyl)phosphine oxide ligand. The glass phase transition behavior of the Eu(III) complex is characterized using differential scanning calorimetry. The transparent amorphous glass shows CPL with extra-large dissymmetry factor of g CPL = 1.2. The brightness of the lumino-glass is one thousand times larger than that of Eu(III) luminophores embedded in polymer films of the same thickness at a Eu(III) concentration of 1 mM. The application of the chiral lanthanide lumino-glass in an advanced security paint is demonstrated.