APL Photonics

Tunable dissipative solitons in a parametric oscillator based on atomic four-wave mixing

Sutapa Ghosh, Brielle E. Anderson, Gregory T. Moille, Zhifan Zhou, K. M. Jones, Paul D. Lett

Published Oct 1, 2026• 0 citations

Abstract

Temporal dissipative solitons are central to nonlinear photonics, yet conventional platforms such as optical fibers and microresonators provide limited dispersion tunability and weak nonlinearities. Here, we demonstrate a highly tunable soliton platform based on atom–light interactions in a rubidium vapor optical parametric oscillator. A continuous-wave pump drives four-wave mixing in the vapor, generating probe and conjugate fields, one of which is fed back through a fiber loop to form the oscillator. By tuning the pump intensity and detuning, we control the dispersive properties and third-order nonlinearity of the medium, enabling the formation of diverse nonlinear states including bright and dark solitons, soliton crystals, dark–bright soliton pairs, platicons, and breather solitons. Unlike conventional systems, solitons emerge spontaneously without cavity scanning or pulsed excitation. The system isolates gain, dispersion, and nonlinearity within the atomic medium, allowing flexible cavity-length tuning without modifying other operating parameters. We introduce the technique of characterizing the solitonic states through the linewidth of the output intensity power spectrum, which remains independent of cavity length and is limited only by the experimental apparatus, indicating a high degree of phase coherence. This contrasts with conventional mode-locked states, for which the linewidth scales inversely with the square of the cavity length. With pulse durations of ∼100 ns determined by the gain bandwidth of the four-wave mixing, the solitons can be directly detected for rapid and complete characterization. This platform offers a versatile route for exploring nonlinear optical dynamics and developing applications in quantum photonics and communication.

DOI: 10.1063/5.0343035

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