Explanation of the competition between O- and E-wave induced stimulated Raman and supercontinuum in calcite under ultrafast laser excitation.

Key optical properties of calcite were measured to unravel the difference between stimulated Raman scattering (SRS) and self-phase modulation (SPM) for the supercontinuum (SC) for ordinary (O) wave and extraordinary (E) wave. These properties are group velocity dispersion, walk-off, spontaneous Raman spectra and cross section, optical 1086 phonon linewidth, nonlinear susceptibility (), steady-state and transient SRS, and SC caused from SPM. These are investigated for O-waves and E-waves from a 2.

Spectroscopic study of optical centers formed in Bi-, Pb-, Sb-, Sn-, Te-, and In-doped germanate glasses.

We have shown that the broadband near-IR (NIR) fluorescence recently discovered in Bi-doped glasses is not specific due solely to Bi ions. Glasses doped with different 6p (Bi, Pb) and 5p (Sn, Sb) ions exhibit very similar behavior characterized by four major spectral peaks observed in two-dimensional excitation-emission plots and the lifetime of metastable level of about 400 micros. Our results challenge the existing models of optical centers in Bi-doped glasses.

Continuous tunable laser operation in both the 1.31 and 1.55 microm telecommunication windows in LiIn(Si/Ge)O4 olivines doped with trivalent chromium.

An ultrawide tuning range from 1160 to 1620 nm for LiInSiO(4) and from 1150 to 1600 nm for LiInGeO(4) crystals has been demonstrated. This is the widest bandwidth and the most near-infrared shifted wavelength range for laser operation ever demonstrated for the Cr(3+) ion. For what is believed to be the first time tunable laser operation was achieved for both the 1.

Direct diode-pumped laser operation of Cr(3+)- doped LiInGeO(4) crystals.

Quasi-continuous wave (cw) laser action has been demonstrated by direct diode pumping of a new extremely broadband Cr(3+)-doped crystal. In contrast to previous works, where large-frame pump lasers have been employed, we have shown that low-power direct diode pumping of LiInGeO(4) is feasible, opening up the way for realizing compact and efficient laser sources for telecommunication applications.

Near-infrared laser operation of Cr3+ centers in chromium-doped LiInGeO4 and LiScGeO4 crystals.

Laser action has been demonstrated in two new tunable Cr3+-doped crystals. Absorption, emission, and excitation measurements for various crystal orientations have been performed for chromium-doped LiInGeO4 and LiScGeO4 single crystals. From the spectroscopic measurements, two optical active centers were identified: tetrahedrally coordinated Cr4+ and octahedrally coordinated Cr3+.