Coherent master equation for laser modelocking

Auro M. Perego, Bruno Garbin, François Gustave, Stephane Barland, Franco Prati, Germán J. De Valcárcel*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Modelocked lasers constitute the fundamental source of optically-coherent ultrashort-pulsed radiation, with huge impact in science and technology. Their modeling largely rests on the master equation (ME) approach introduced in 1975 by Hermann A. Haus. However, that description fails when the medium dynamics is fast and, ultimately, when light-matter quantum coherence is relevant. Here we set a rigorous and general ME framework, the coherent ME (CME), that overcomes both limitations. The CME predicts strong deviations from Haus ME, which we substantiate through an amplitude-modulated semiconductor laser experiment. Accounting for coherent effects, like the Risken-Nummedal-Graham-Haken multimode instability, we envisage the usefulness of the CME for describing self-modelocking and spontaneous frequency comb formation in quantum-cascade and quantum-dot lasers. Furthermore, the CME paves the way for exploiting the rich phenomenology of coherent effects in laser design, which has been hampered so far by the lack of a coherent ME formalism
Original languageEnglish
Article number311
Number of pages1
JournalNature Communications
Issue number1
Publication statusPublished - 16 Jan 2020

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