Fiber optic plasmonic sensors: Providing sensitive biosensor platforms with minimal lab equipment.

A simple, convenient, and inexpensive method to fabricate optical fiber based biosensors which utilize periodic hole arrays in gold films for signal transduction is reported. The process of hole array formation mainly relies on self-assembly of hydrogel microgels in combination with chemical gold film deposition and subsequent transfer of the perforated film onto an optical fiber tip. In the fabrication process solely chemical wet lab techniques are used, avoiding cost-intensive instrumentation or clean room facilities.

Large fluctuations at the lasing threshold of solid- and liquid-state dye lasers.

Intensity fluctuations in lasers are commonly studied above threshold in some special configurations (especially when emission is fed back into the cavity or when two lasers are coupled) and related with their chaotic behaviour. Similar fluctuating instabilities are usually observed in random lasers, which are open systems with plenty of quasi-modes whose non orthogonality enables them to exchange energy and provides the sort of loss mechanism whose interplay with pumping leads to replica symmetry breaking. The latter however, had never been observed in plain cavity lasers where disorder is absent or not intentionally added.

Hierarchical multicolor nano-pixel matrices formed by coordinating luminescent metal ions to a conjugated poly(4'-octyl-2',6'-bispyrazoyl pyridine) film via contact printing.

We introduce a cost-effective, yet feasible reactive printing approach namely, "coordination chemistry at the conjugated ligand polymer surface". By using a contact printing technique we selectively fabricated high resolution nano-pixel configurations consisting of red, blue and green (R,G,B) colors arranged in a hierarchical three-dimensional fashion. For this, we have synthesized a novel blue emitting conjugated ligand polymer, [poly(4'-octyl-2',6'-bispyrazoyl pyridine)] ( ~ 7-8 KDa) having a tridentate ligand in its repeating unit which forms a thin film prone of binding metal ions.

Fabrication of high-resolution 4,8(2) -type archimedean nanolattices composed of solution processable spin cross-over Fe(II) metallosupramolecular polymers.

This paper presents the synthesis of two highly soluble Fe(II) metallosupramolecular polymers with two counter anions from a novel back-to-back coupled hybrid ligand. The spin cross-over (SCO) temperature of polymers with BF4 and ClO4 counter anions is T1/2 = 313 K and T1/2 = 326 K, respectively. By following the top-down approach, one of the polymers (with ClO4 counter anion) is successfully solution processed using a lithographically controlled wetting technique to create laser readable high-resolution Archimedean (4,8(2) ) nanolattices (consist of diamagnetic octagons and SCO squares).

Planar active organic waveguide and wavelength filter: self-assembled meso-tetratolylporphyrin hexagonal nanosheet.

We have fabricated nearly monodispersed nanocrystalline sheet waveguides from a well-known red emitting meso-tetratolylporphyrin molecule (1) by following a bottom-up solvent assisted self-assembly technique. The nano-sheets thickness is in the range of 110-180 nm. Localized laser illumination showed excitation position dependent exciton polariton (653 and 719 nm) propagation behavior of the sheets.

Micropatterning of metallopolymers: syntheses of back-to-back coupled octylated 2,6-bis(pyrazolyl)pyridine ligands and their solution-processable coordination polymers.

This paper presents a 10-step synthetic route for the preparation of a series of new back-to-back coupled 2,6-bis(pyrazol-1-yl)pyridine (bpp) ligands (L0-L3) decorated with tetraoctyl chains. Ligand L1 self-assembles with Zn(2+) ion to form a highly soluble metallo-supramolecular polymer 1 with M(n) ∼ 9600 g/mol. To demonstrate the processability of polymer 1, by following a "top-down" approach periodic one-dimensional fluorescent microstripes were fabricated on a silica substrate.