Abstract

We present an optical parametric amplifier that is seeded by a wavelength tunable cw laser diode. By using the idler tunable near transform limited pulses with pulse durations between 190 fs and 230 fs are obtained directly without the need for any compression. Those idler pulses have been amplified in a second stage up to 7.2 µJ pulse energy at 50 kHz pulse repetition frequency. Additionally, we characterized the idler of the second stage that offers the tuning range of the cw seed and has similar pulse energies and durations. Furthermore, we varied the pump pulse duration that allowed the variation of the near transform limited idler pulses. Hence, this scheme provides a source for ultrashort pulses near their transform limit with variable pulse duration and center wavelength.

© 2010 Optical Society of America