2.7mW output of emerald laser pumped by laser diode - art. no. 60280M

Emerald [Cr3+ :Be3Al2Si6O18] is a negative uniaxial crystal and belongs to the hexagonal system with a space group D-6h(2) (P6/mcc).Owing to transitions of the Cr3+ ion, emerald crystal is a more efficient wide band tunable laser medium among many Cr3+-doped lasing mediums. Compared with alexandrite, emerald has a more complex crystal structure and a weaker crystal field. The emission cross-section of emerald is approximately four times larger than of alexandrite. Its melting point is 1470 degrees C, which is 400 degrees C lower than that of alexandrite. The thermal conductivity of emerald is 0.04W/cm(-1)deg(-1), being nearly six times less than that of alexandrite([1]). Since 1982, emerald lasers have been achieved running with pumping by flash lamps, shot pulse laser generated by a Nd:YAG pumped Ba(NO3)(2) Raman laser, an argon laser and a krypton CW laser[1-7]. Ref. 6 reported that the laser output-slope efficiency achieved 64% with the use of higher optical quality emerald crystal and high efficient resonator. But nowadays, emerald lasers have received only marginal application due to producing adequate size crystal with difficulty, limitation of growth method, poor optical quality and intense thermal effect. In the course of our studies on the growth conditions of emerald crystals in a ([8-9]) new hydrothermal solution, the quality of emerald crystals has been improved from gem quality to optical quality. With the development of high power laser diode and the improvement of emerald quality, the LD pumping emerald laser is essential to study. In this paper, we reported an emerald CW laser at 731nm wavelength pumped by 660nm LD and its performance. According to our knowledge, this is first paper about LD pumping emerald laser.