What defines how a free running pulse is created?

A free running pulse in a laser is characterized by its ability to emit photons in powerful bursts rather than in a continuous manner. This pulsed emissions occur spontaneously due to the laser's internal gain medium and its ability to build up energy before releasing it suddenly as a pulse. The nature of this pulsing allows for high peak power, which is essential for various applications in fields like medicine and materials processing.

In contrast, continuously emitting photons relates to a continuous-wave (CW) laser operation, where energy is always being emitted, making it distinct from the pulse operation. Using a shutter to interrupt the beam pertains to controlling the output but does not define the inherent mechanism of pulse generation in a free running laser. Lastly, maintaining a continuous beam also describes a CW setup rather than a free running pulse, which is defined by its episodic energy release rather than a steady state.