Q-switching of a Tm, Ho:KLu(WO4)2 microchip laser by a graphene-based saturable absorber. (17th December 2015) - Serres, J M
Abstract: The first Ho microchip laser passively Q-switched using a graphene-based saturable absorber is demonstrated based on a Tm, Ho:KLu(WO4 )2 crystal cut along the N g -axis. A maximum average output power of 74 mW is extracted from the diode-pumped laser at 2061 nm with a slope efficiency of 4%. Pulses as short as 200 ns with an energy of ~0.2 μ J are obtained at a repetition rate of 340 kHz. The energy transfer (ET), 3 F4 (Tm 3+ ) ↔ 5 I7 (Ho 3+ ) is studied, yielding ET parameters of P 28 = 1.69 and P 71 = 0.15 × 10 −22 cm 3 μ s −1, revealing the strong prevalence of direct ET.