2.54 W 1535 nm KTiOAsO₄optical parametric oscillator within a diode-side-pumped acousto-opticallyQ-switched Nd : YAG laser

Abstract

We report a nanosecond singly resonant intracavity optical parametric oscillator (OPO) emitting at 1535 nm. This OPO is based on a type II non-critically phase-matched KTiOAsO4 (KTA) crystal. A diode-side-pumped acousto-optically Q-switched Nd : YAG laser is used as the pumping source. With a laser diode power of 96.3 W and a pulse repetition rate of 10 kHz, we obtain a signal power of 2.54 W, corresponding to an optical-to-optical conversion efficiency of 2.6%. This is the highest efficiency reported for intracavity KTA OPOs with diode-side-pumping configurations. The pulse width is 5.01 ns and the peak power is 50.7 kW. The stability of the signal power is measured to be better than 3% during 2 h operation.

High-power LD end-pumped intra-cavity Nd:YAlO3/KTiOAsO4 optical parametric oscillator emitting at 1562 nm

“…However, the output power was below 1.5 W for LD end-pump systems [8][9][10][11], and the diode to signal conversion efficiency was less than 5% for LD side-pump systems [12,13]. at 1535 nm and the efficiency of 2.6% for the LD sidepumped KTA-OPO [13]. More recently, we reported an efficient OPO generation with design which was capable of compensating mode mismatch between fundamental cavity and OPO cavity [14].…”

“…In recent years, KTA-OPO driven by the Q-switched Nd-doped laser sources have been extensively studied. However, the output power was below 1.5 W for LD end-pump systems [8][9][10][11], and the diode to signal conversion efficiency was less than 5% for LD side-pump systems [12,13]. In 2008, H.T.…”

Nd : YAG pumped tunable singly resonant optical parametric oscillator in mid-infrared

“…But from this OPO the maximum output energy achieved at 3.6 µm was 4.6 mJ at 55 mm cavity length and 85 grooves mm −1 grating applying 42.6 mJ pumped beam energy. In an intra-cavity OPO using a KTA crystal by Wang et al [18] at 1535 nm an energy output of 2.54 W at 10 kHz repetition rate has been realized applying a pump beam energy of 96.3 W. The output energy using a KTA crystal in different nonlinear interactions reported so far has been summarized in table 3…”

“…But it is to be noted here that from this reported OPO the maximum conversion efficiency of the pump beam energy to the generated idler beam energy at 3.6 µm achieved was 10.8% at 55 mm cavity length and 85 grooves mm −1 grating. In an intra-cavity OPO using a KTA crystal by Wang and co-workers [18] and applying a pump beam energy of 96.3 W at 10 kHz repetition rate the output energy of 2.54 W was realized, which corresponds to the conversion efficiency of 2.6%. The conversion efficiency of the pump beam energy to the generated radiation energy using a KTA crystal in different nonlinear interactions reported so far has been summarized in table 3.…”

Efficient high-pulse-energy eye-safe laser generated by an intracavity Nd:YLF/KTP optical parametric oscillator: role of thermally induced polarization switching

“…Generally speaking, the multiple round trips can cause the polarization state of the fundamental beam to be changed by the birefringence in the laser cavity. The birefringence-induced polarization switching may be the main mechanism why efficient intracavity nonlinear frequency conversions, such as harmonic generations [9][10][11][12] and optical parametric oscillations [13][14][15][16][17], can be successfully realized by using the optically isotropic materials without any active polarization control in the optical resonator. For example, the output power as high as 36.9 W at 532 nm with the Nd:YAG crystal has been achieved by using an intracavity frequency doubling configuration [12], and the intracavity Nd:YAG/KTA optical parametric oscillator (OPO) has efficiently generated the eye-safe radiation at 1.54 µm with the output power up to 12.7 W [17].…”