Hybrid plasmonic-photonic crystal formed on gel-immobilized colloidal crystal via solvent substitution

Abstract

Gel-immobilized colloidal crystals were prepared to obtain hybrid plasmonicphotonic crystals, in which electric field enhancement to a greater extent than that due to localized surface plasmons (LSP) alone was expected due to coupling between LSP and the photonic band. Polystyrene colloidal crystals immobilized by the N-(hydroxymethyl)acrylamide gel were immersed in an aqueous dispersion of gold nanoparticles (AuNPs). Then, the gelimmobilized colloidal crystals were picked out and immersed in an ionic liquid mixture. The surfaces of the gel-immobilized colloidal crystals immersed in the AuNP dispersion were observed via scanning electron microscopy after this solvent substitution. The lattice spacing of the colloidal crystal varied as the composition of the ionic liquid mixture was changed. The composition was determined so that the photonic band gap wavelength coincided with the LSP wavelength. Further, the reflection spectra were measured. Thus, we successfully prepared a hybrid plasmonic-photonic crystal.

Ptychographic X‐Ray Imaging of Colloidal Crystals

“…Colloidal crystals are being actively employed as an important model system to study melting, freezing, and solid‐solid phase transitions as a function of osmotic pressure and anisotropy of interparticle interaction due to particle shape, patchiness, or dipolar interactions . The flexibility of colloidal crystals and their response to external stimuli along with their unique optical properties such as the strongly pronounced structural color and photonic band gap makes them attractive for many applications . Moreover, defects, which determine the mechanical properties of many engineering materials such as metals, can be studied with “atomic” resolution using colloidal crystals …”

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] The flexibility of colloidal crystals and their response to external stimuli [16][17][18] along with their unique optical properties such as the strongly pronounced structural color and photonic band gap makes them attractive for many applications. [19][20][21][22][23][24][25] Moreover, defects, which determine the mechanical properties of many engineering materials such as metals, [26] can be studied with "atomic" resolution using colloidal crystals. [27][28][29] The high penetration depth of X-rays makes them an ideal tool to access important statistically averaged spatial information about the colloidal crystal structure and disorder over macroscopic sample volume.…”