In 1976 Byer proposed using stimulated rotational Raman scattering in hydrogen gas as an efficient method of frequency conversion in the infrared.' In particular, it was noted that stimulated Raman scattering in para-H 2 gas with a CO2 laser pump generates 16-gm radiation, which is of potential use for UF 6 isotope enrichment. It was subsequently learned that others have also suggested stimulat...

Raman spectroscopy is among the primary techniques for the characterisation of graphene materials, as it provides insights into the quality of measured graphenes including their structure and conductivity as well as the presence of dopants. However, our ability to draw conclusions based on such spectra is limited by a lack of understanding regarding the origins of the peaks. Consequently, tradi...

We report the demonstration of the first silicon Raman laser. Experimentally, pulsed Raman laser emission at 1675 nm with 25 MHz repetition rate is demonstrated using a silicon waveguide as the gain medium. The laser has a clear threshold at 9 W peak pump pulse power and a slope efficiency of 8.5%.

Raman Amplifiers (RAs) are a group of amplifiers which have various applications in optical communications. Data transmission media utilized for RAs are optical fibers operating in nonlinear regime. We present the performances and characteristics of RAs by utilizing a set of coupled differential equations and numerical simulations. Two types of fibers with different gain characteristics, german...

Spectral broadening of the fundamental field in intracavity Raman lasers is investigated. The mechanism for the spectral broadening is discussed and the effect is compared in two lasers using Raman crystals with different Raman linewidths. The impact of the spectral broadening on the effective Raman gain is analyzed, and the use of etalons to limit the fundamental spectral width is explored. It...

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...

In this paper, we report record nanosecond output energies of gain-switched Cr:ZnSe lasers pumped by Q-switched Cr:Tm:Ho:YAG (100 ns @ 2.096 μm) and Raman shifted Nd:YAG lasers (7 ns @ 1.906 μm). In these experiments we used Brewster cut Cr:ZnSe gain elements with a chromium concentration of 8x10 cm. Under Cr:Tm:Ho:YAG pumping, the first Cr:ZnSe laser demonstrated 3.1 mJ of output energy, 52% s...

We present experimental results on the suppression of a complete Raman cascade in a holey fiber by using gain competition with parametric processes. The modulation instabilities which strongly affect the stimulated Raman scattering (SRS) gain are induced by two pump wavelengths (532 nm, 1064 nm) placed far and quasi symmetrically on each side of the zero dispersion wavelength (ZDW) of the fiber...