We study the effect of polarized laser annealing on the crystalline structure of individual crystalline-amorphous core-shell silicon nanowires (NWs) using Raman spectroscopy. The crystalline fraction of the annealed spot increases dramatically from 0 to 0.93 with increasing incident laser power. We observe Raman lineshape narrowing and frequency hardening upon laser annealing due to the growth ...

We report a synchronously-pumped femtosecond diamond Raman laser operating with a tunable second-Stokes output. Pumped using a mode-locked Ti:sapphire laser at 840-910 nm with a duration of 165 fs, the second-Stokes wavelength was tuneable from 1082 - 1200 nm with sub-picosecond duration. Our results demonstrate potential for cascaded Raman conversion to extend the wavelength coverage of standa...

Introduction: There is a need for an instrument that can be used for remote in situ identification of biogenic and a-biogenic minerals, various types of ices, organic materials etc. on planetary surfaces. The potential for measuring remoteRaman spectra of organic [1] and inorganic materials and minerals [2] with a small telescope and CW lasers have been demonstrated. Pulsed-laser Raman spectros...

Raman sensing and microscopy are among the most specific optical technologies to identify the chemical compounds of unknown samples, and to enable label-free biomedical imaging. Here we present a method for stimulated Raman scattering spectroscopy and imaging with a time-encoded (TICO) Raman concept. We use continuous wave, rapidly wavelength-swept probe lasers and combine them with a short-dut...

We measured Raman scatterings from various single-walled carbon nanotube (SWNT) samples over a wide temperature range (4-1000 K). The G-band peaks showed clear temperature dependence, namely decrement in the Raman shift frequency and broadening of the peak width as temperature increases. The main G-band peak (G peak) showed universal temperature dependence in Raman shift for the various SWNT sa...

Lasers are instrumental in advanced bioimaging and Raman spectroscopy. However, they are also well known for their destructive effects on living organisms, leading to concerns about the adverse effects of laser technologies. To implement Raman spectroscopy for cell analysis and manipulation, such as Raman-activated cell sorting, it is crucial to identify nondestructive conditions for living cel...

Nanogap devices have applications in single molecule sensing and single molecule transistors. Nanogap devices comprised of a gold nanowire with a nanoscale gap containing C60 were fabricated using electromigration on a silicon substrate. Raman spectra were obtained for various features of this device in order to detect the presence of C6o and study its electronic properties. The 532 nm laser so...

in this research zinc oxide (zno) nano-crystalline powders were prepared by sol-gel method using zinc acetate. the zno nanoparticles were characterized by x-ray diffraction (xrd), scanning electron microscopy (sem), ultraviolet-visible (uv-vis), fourier transform infra-red (ft-ir) and energy dispersive x-ray (edx) spectroscopy. the structure of nanoparticles was studied using xrd pattern. the c...

A solution based laser direct write technique for patterning of glass substrates with silver nanoparticles is presented. Photoreduction of an AgNO3 solution, by nanosecond UV laser pulses, produces a source solution of silver particles. A glass substrate is then inserted into this solution and the laser is scanned over its surface. Laser-induced fragmentation of the silver particles in the solu...

We have continued our precision studies of laser induced stimulated resonance Raman interactions in a sodium atomic beam with emphasis on Ramsey's method of separated oscillatory fields. We observed Raman-Ramsey fringes for a field separation of up to 30 cm, and the data were consistent with theoretical predictions. We have also been investigating the performance of a clock based on this intera...