Hysteresis effects in the mode locking of a He-Ne laser by a Ne discharge cell

We have observed the existence of hysteresis effects associated with the mode locking of a He-Ne laser operating at 6328 Å by a Ne cell when appropriate excitations, losses, lengths, and positions of both laser tube and Ne cell are chosen. The hysteresis effects manifest themselves in the pulsing rate, the pulse-width, and the power output.