Multidimensional optical techniques, the focus of this special issue, are analogues of their NMR counterparts; that is, rather than using spin transitions as little spies within a molecule, we use vibrational or optical transitions. Similar to NMR, the spectroscopic states often respond in a very sensitive way to their chemical environment. By modeling the coupling of one of these states to eit...

We present the results of optical spectroscopy of a newly discovered H ii region residing in the H i gas cloud located between the dwarf irregular galaxy UGC 7636 and the giant elliptical galaxy NGC 4472 in the Virgo Cluster. By comparing UGC 7636 with dwarf irregular galaxies in the field, we show that the H i cloud must have originated from UGC 7636 because (1) the oxygen abundance of the clo...

Colloidal crystals offer a promising route for the formation of three-dimensional photonic crystals. The primary constraint in working with these materials is the disorder present in these self-assembled materials. Sphere vacancies, line dislocations, and random position errors all lead to a degradation in the optical properties. It is important to characterize these effects so as to guide furt...

A novel straightforward, accessible and efficient approach is presented for performing hyperspectral time-domain diffuse optical spectroscopy to determine the optical properties of samples accurately using geometry specific models. To allow bulk parameter recovery from measured spectra, a set of libraries based on a numerical model of the domain being investigated is developed as opposed to the...

We study the nonlinear optical response of a fishnet structure-metamaterial all-optical switching device that exhibits two near-infrared negative-index resonances. We study and compare the nonlinear optical response at both resonances and identify transient spectral features associated with the negative index resonance. We see a significantly stronger response at the longer wavelength resonance...

Excitons represent collective optical excitations in which the motions of electrons belonging to different chromophores are correlated. We discuss the utility of the notion of entanglement commonly used in quantum information processing, in the description of these excitations. A distinction is made between some apparent entanglement effects associated with the linear response that may be remov...

A novel approach using microstructured optical fiber and Raman spectroscopy for identifying acetone is reported. This technique combines the advantage of small sampling volume of microstructured optical fiber and the specificity of Raman spectroscopy.

Polyurethane closed cell (PUCC)/SiO2 nanocomposites have been prepared by using in situ polymerization approach. The third-order optical nonlinearities of PUCC/SiO2 nanocomposites, dissolved in DMF are characterized by Z-scan technique at the measurement wavelength of 532 nm. The nonlinear refractive (NLR) indices and nonlinear absorption (NLA) coefficients of samples were calculated from close...