Mode-Locked Laser and the 180° Pulse

Abstract

We suggest that the pulses traveling back and forth in a mode-locked laser oscillator are 180\ifmmode^\circ\else\textdegree\fi{} pulses and show that experimental measurements of the width of the pulse in a self-locked He-Ne laser as a function of intensity agree well with the calculated 180\ifmmode^\circ\else\textdegree\fi{} pulse widths for the medium.