A long-period fiber-grating sensor with a high strain sensitivity of -7.6 pm/microepsilon and a low temperature sensitivity of 3.91 pm/ degrees C is fabricated by use of focused CO(2) laser beam to carve periodic grooves on a large- mode-area photonic crystal fiber. Such a strain sensor can effectively reduce the cross-sensitivity between strain and temperature, and the temperature-induced strain error obtained is only 0.5 microepsilon/ degrees C without using temperature compensation.

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The photoinduced regio- and enantioselective coupling of naphthols and derivatives thereof is achieved in the confined chiral coordination space of a Ru metalloligand based cage. The racemic or enantiopure cages encapsulate naphthol guests, which then undergo a regiospecific 1,4-coupling, rather than the normal 1,1-coupling, to form 4-(2-hydroxy-1-naphthyl)-1,2-napthoquinones; moderate stereochemical control is achieved with homochiral cages. The photoreactions proceed under both aerobic and anaerobic conditions but through distinct pathways that nevertheless involve the same radical intermediates. This unusual dimerization constitutes a very rare example of asymmetric induction in biaryl coupling by making use of coordination cages with dual functionality-photoredox reactivity and stereoselectivity.

Long period fiber gratings in hollow-core air-silica photonic bandgap fibers were produced by use of high frequency, short duration, CO 2 laser pulses to periodically modify the size, shape and distribution of air holes in the microstructured cladding. The resonant wavelength of these gratings is highly sensitivity to strain but insensitive to temperature, bend and external refractive index. These gratings can be used as stable spectral filters and novel sensors.

A simple method for fabricating selective injection microstructured optical fibers (MOFs) using a conventional fusion splicer is described. The effects of fusion current, fusion duration and offset position on the hole collapse property of the MOFs are investigated. With this method, the central hollow-core and the holes in the cladding region can be selectively infiltrated, which allows for the fabrication of novel hybrid polymer-silica and liquid-silica MOFs for various applications.