First-principles modeling reveals that dynamical lasing-inversion coupling generates exceptional points in optical cavities, suggesting new pathways for tunable photonics and spectroscopy.
Key Points
To identify the theoretical mechanism that overcomes strong gain competition and drives a second optical mode to threshold near exceptional points.
Formulated a Bloch coupled-mode theory derived from first principles.
Modeled dynamical interactions between the lasing field, population inversion, and an unpumped dark cavity mode.
Dynamical coupling between the lasing field and population inversion induces additional exceptional points above the lasing threshold.
The resulting spectral structure controls switching between single-mode lasing and frequency combs with distinct repetition rates.