Precision of the synchronization of subnanosecond laser pulses with brief periodic Q switching

Experiments and numerical simulations have been carried out to determine the synchronization precision for a laser with brief periodic Q switching which has the ability to synchronize ultrashort output pulses with an external electrical control pulse. For a generation pulse length of 1–2 μs, the physical limit on the synchronization precision is 0.04T, where T is the axial period of the cavity, when the rise time of the Q is 2T for the pulse train. The instability of the synchronization is due primarily to an instability of the rise time and the errors within which the front is coordinated with external processes through electrical sync pulses. When an air-gap switch is used to form the electrical control signal, control pulses with a rise time ~ 20 ns lead to an instability of less than 1 ns in the synchronization, according to measurements.