Area theorem for coherent pulse propagation in a quantum-dot laser

We extend the area theorem toward the analytical description of the coherent pulse propagation in a quantum-dot (QD) laser medium in a ring-cavity setup. We apply the derived area theorem to demonstrate the appearance of the stable coherent mode-locking regime in a single-section ring-cavity QD laser. The paper findings showcase the possibility of making compact solid-state sources of ultrashort pulses with pulse duration well beyond the gain bandwidth limit.