Comparative investigation of diode pumping for continuous-wave and mode-locked Cr^3+:LiCAF lasers

Femtosecond tuning of Cr:colquiriite lasers with AlGaAs-based saturable Bragg reflectors

“…Cr 3þ :colquiriite (Cr 3þ :LiSAF [2], Cr 3þ :LiSGaF [3], and Cr 3þ : LiCAF [4]) lasers are a promising low-cost alternative to Ti:sapphire due to (i) their broad emission bands covering the 750-1050 nm spectral region and (ii) the possibility of direct diode pumping with low-cost laser diodes emitting around 650 nm [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Besides enabling a significant reduction in cost, direct pumping with high-brightness diodes also greatly improves electrical-to-optical conversion efficiency.…”

“…Advantages of using SBRs instead of KLM include self-starting, robust mode-locked operation with long-term stability, immunity to environmental fluctuations, reduced cavity alignment sensitivity, and higher efficiencies. Using low-cost, single-mode laser diodes that emit around 650 nm (optical power of ∼150 mW), and SBRs for mode-locking, turn-key femtosecond Cr:colquiriite lasers, with sub-100-fs pulses and 20-40 kW peak power were obtained with electrical-to-optical conversion efficiencies above 8% [17,19]. Once aligned, these lasers are quite stable and operate as a turn-key system for days to weeks, requiring little adjustment due to mechanical/thermal misalignments.…”

Generation of 15 nJ pulses from a highly efficient, low-cost multipass-cavity Cr^3+:LiCAF laser

“…:LiSGaF can be directly diode-pumped near 650 nm and enable the development of low-cost and highly efficient lasers operating near 800 nm [1][2][3][4][5][6][7][8][9][10][11]. Furthermore, the broad gain bandwidths of these media enable the generation of pulses as short as 10 fs [5,7].…”

“…Furthermore, the broad gain bandwidths of these media enable the generation of pulses as short as 10 fs [5,7]. Possible laser diode pump sources include diode arrays [4], broad-stripe single-emitter diodes [3,[7][8][9]11] as well as single transverse-mode diodes [6,10,11]. The peak powers obtainable from colquiriite media can be increased by scaling the output energy and/or reducing the pulsewidths.…”

“…Although higher peak powers can be obtained with multimode diode pumping [4,9], single mode pumping has the advantages of lower cost, better matching between pump and laser modes, significantly lower lasing thresholds, reduced thermal effects and higher efficiency [10,11]. For example, mode-locked optical-to-optical conversion efficiencies of ∼28% have been demonstrated with single-mode diode pumping [10], whereas only 6% and 7.5% efficiency could be obtained with arrays [4], and broad-stripe single-emitter diodes, respectively [9].…”