A sub-100 fs self-starting Cr:forsterite laser generating 1.4 W output power.

Without cavity dumping or external amplification, we report a femtosecond Cr:forsterite laser with a 1.4 W output power and 2 W in continuous wave (CW) operated with a crystal temperature of 267 K. In the femtosecond regime, the oscillator generates Kerr-lens-mode-locked 84 fs pulses with a repetition rate of 85 MHz, corresponding to a high 16.5 nJ pulse energy directly from a single Cr:forsterite resonator. This intense femtosecond Cr:forsterite laser is ideal to pump varieties of high power fiber light sources and could be thus ideal for many biological and spectroscopy applications.

Coherent anti-Stokes Raman scattering of two-phonon complexes in diamond.

Coherent anti-Stokes Raman scattering (CARS) associated with the second-order Raman process has been confirmed in diamond. Frequency dependence of CARS was analyzed using two-color synchronously-generated picosecond pulses. Resonance enhancement of chi((3)) was observed at an energy shift corresponding to the overtone Sigma branch (K point) phonon, as well as the fundamental Raman-active Gamma((25+)) phonon. The excitation spectrum of CARS at the two-phonon resonance region showed dispersive dependence, reflecting the interference of resonant CARS and nonresonant four-wave mixing scattering.