ABSTRACT
We propose a novel device that exhibits nonreciprocity in optical reflection or transmission. The device is formed by two frequency-doubling crystals and a suitable dichroic mirror or a filter. The nonreciprocity may exceed 100 and be accompanied by nonlinear reflection or transmission. Applications in unidirectional and mode-locked lasers are discussed.
ABSTRACT
A second-harmonic nonlinear mirror formed by a LiIO(3) frequency doubler and a dichroic output mirror is employed to mode lock the 1.34-microm transition of a pulsed Nd:YAlO(3) laser. Pulses of 15-ps duration are reliably generated simultaneously at 1.34 and 0.67 microm.
ABSTRACT
We present a computer simulation of the mode-locking process in a pulsed Nd:YAG laser with a nonlinear mirror based on second-harmonic generation. For the first time to our knowledge, a frequency-domain description of the passive mode-locking process is presented, which provides complete information for the amplitude and phase evolution of the individual modes. The mode locking is described as being due to the interaction of the longitudinal modes in the nonlinear mirror through second-harmonic and sum- and difference-frequency generation.
ABSTRACT
The influence of the group-velocity mismatch between the fundamental and the second harmonic in the frequency-doubling nonlinear mirror is investigated theoretically. The nonstationary analysis provides an estimation for the maximum pulse-shortening capabilities of the device when it is used as a passive mode locker. The pulse-shape deformation is also investigated.
ABSTRACT
A vacuum photodiode was used to drive a Pockels cell directly in an optical-feedback arrangement. This technique was used to achieve Q switching and a single-longitudinal-mode operation in a flash-lamp-pumped Nd:YAG laser. Synchronization within 2 ns with an external short-pulse laser source was demonstrated.