Nd:YVO_4 amplifier for ultrafast low-power lasers

Abstract

An Nd:YVO4 amplifier consisting of two modules end pumped at 808 nm at 30 W total absorbed power has been designed for efficient, diffraction-limited amplification of ultrafast pulses from low-power seeders. We investigated amplification with a 50 mW, 7 ps Nd:YVO4 oscillator, a 2 mW, 15 ps Yb fiber laser, and a 30 mW, 300 fs Nd:glass laser. Output power as high as 9.5 W with 8 ps pulses was achieved with the 250 MHz vanadate seeder, whereas the 20 MHz fiber laser was amplified to 6 W. The femtosecond seeder allowed extracting Fourier-limited 4 ps pulses at 7 W output power. To our knowledge, these are the shortest pulses from any Nd:YVO4 laser device with at least 7 W output power. This suggests a novel approach to exploit the gain bandwidth of vanadate amplifiers with high output power levels. Such amplifier technology promises to offer an interesting alternative to high-power thin disk oscillators at few picoseconds duration, as well as to regenerative amplifiers with low-repetition-rate fiber seeders.

Direct amplification of a nanosecond laser diode in a high gain diode-pumped Nd:YVO_4 amplifier

“…Nd∶YVO 4 amplifiers pumped at 808 nm have already been proven to deliver high gain. Output powers of around 10 W with gains of about 200 have been obtained with a two stage amplifier and a microchip laser or a fiber laser as seed source [16,17]. Using a more complex setup with a grazing incidence configuration with 4 pass and a phase conjugation mirror, a high gain of 41 dB has also been obtained with 26 W output power [18].…”

Power Scaling in a Diode-End-Pumped Multisegmented Nd:YVO<inline-formula><tex-math>$_{\bf 4}$</tex-math> </inline-formula> Laser With Double-Pass Power Amplification

“…It can be obviously seen that the power gain achieved in the double-pass MOPA architecture is generally larger than that obtained from the single-pass MOPA architecture, especially for the low input seed power. Experimental results also manifestly reveal that the power gain decreases by increasing the input seed power for both configurations, this is a typical behavior for the power amplifier [13], [15], [16]. When the input seed power is changed from 0.8 to 50 W, the power gains are experimentally found to decrease from 8 to 2.16 for the double-pass MOPA frame and from 2.95 to 1.76 for the single-pass MOPA frame, respectively.…”

“…To date, most of the Nd:YVO 4 amplifiers are based on the single-pass configuration [12]- [14]. However, some recent works have shown that the double-pass architecture seems to be a more efficient design for scaling the output power of the pulsed oscillator [15], [16]. In this work, an efficient high-power MOPA based on the multi-segmented Nd:YVO 4 crystal is successfully realized for emitting output power greater than one hundred watts in the continuous-wave operation.…”

Low repetition rate, hybrid fiber/solid-state, 1064 nm picosecond master oscillator power amplifier laser system

“…7. This scheme was already investigated in great detail in previous work [20] and proved to be suitable for amplification of seeders providing few milliwatts average power.…”