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We will give an overview of recently observed analogies between the transport of electrons and light waves and show how complex photonic materials, ranging from periodic to disordered structures can be applied as photonic devices.
A simple first-principle analytical derivation of the permanent matrix elements of the dipole moment responsible for most of the resonant nonlinearities in III-V and II-VI semiconductors is presented.
The first hyperpolarizabilities (beta) of several ldquoH-shapedrdquo second-order nonlinear optical chromophores measured by hyper-Rayleigh scattering technique exhibit much higher values than those of their monomers with slight absorption red shifting because of intra-molecular interactions.
A compact sensor for physically sorting bio-aerosols based on fluorescence spectra excited using UV-LED arrays is presented. The optical system integrates electronics for real-time processing of spectral data and a miniaturized aerodynamic deflector for particle separation.
We present a new and very simple method for wavelength and line width measurement with a resolution in the femtometer range. The method is based on the narrow bandwidth of Brillouin scattering in optical fibers.
Increased scattering and decreased diffraction loss introduced by symmetrically etched wedge patterns in proton-implanted vertical-cavity surface-emitting lasers are investigated. We show proper wedge design leads to improved fundamental-mode output power, decreased threshold, and increased efficiency.
Recovery of electrons from excited neutral donor states in GaAs is time-resolved using a novel optical readout technique and pulsed terahertz excitation. Long (0.1-1 mus) 2P state lifetimes are measured at various magnetic fields.
The relationship between the physical fabrication of asymmetric cladding surface etched DBR structures and the resulting optical characteristics are characterized. The effective index step and DBR scattering loss for these structures is determined.
In frequency-domain optical coherence tomography the tissue scattering function is recovered by a simple inverse Fourier transform (IFT) of the measured power spectrum. Instead, we report that taking an IFT of the square-root of the same power spectrum improves the axial-resolution and reduces the auto-correlation noise.
Near-IR negative index metamaterials with substantially improved optical performance are numerically demonstrated and experimentally verified. The scaling of this structure to visible wavelengths is also discussed.
Time-resolved mid-infrared-pump, optical-probe differential transmission spectroscopy directly reveals electron dynamics in n-doped quantum dots infrared detector structure. Capturing and intradot relaxation time were measured. Nanosecond-scale dynamics in the n=1 state was also observed.
By combining electron diffraction with Rayleigh scattering spectroscopy, we determine the physical structure and optical transition energies of individual single-walled carbon nanotubes. This permits study of the energy-level structure as a function of nanotube chirality.
Directional ultraviolet lasing at room temperature in 3D ZnO photonic crystals is reported. Comparison of measured optical properties with the calculated band structures shows that lasing occurs due to slow-propagating modes in high-order photonic bands.
Orientational dynamics of nematic liquid crystals are studied using optical Kerr effect experiments in isotropic phase. A combined theory of mode coupling theory and Landau-de Gennes theory is successful to reproduce the data.
We demonstrate how a strong coherent backward wave can be generated by forward propagating beams only. It is a dispersion effect resulting from probing a counter-propagating coherence grating by properly detuned fields.
We investigate slow-light enhancement of stimulated Raman scattering in monolithic silicon photonic crystal defect waveguides. The applied Bloch-Floquet formalism demonstrates remarkable gain enhancements up to 104 at the band-edges, while considering disorder, absorption and coupling.
Scanning probe vibrational Raman microscopy with single molecule sensitivity is demonstrated. This is facilitated by unique optical antenna properties of the metallic probe tip and resulting plasmonic tip-sample coupling providing sub-10 nm spatial resolution.
Conversion of cw light at 1.56 mum to Stokes wave was achieved with an efficiency of 27% using a 5-m-long As2Se3 chalcogenide fiber. Stokes shift and gain coefficient were 7.95 GHz and 6.08 times 10-9 m/W, respectively.
Optical coherence tomography (OCT) performs resolution imaging in biological tissues and materials. Recent advances enable order of magnitude increases in imaging speed as well as resolutions, enabling a wide range of materials and medical applications.
We suggest a new efficient method of generation of intense (micro-J) short (fs-ns) THz pulses via coherent scattering of infrared radiation in atomic and molecular gases (f.e. Rb, methanol, and others) at room temperature.
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