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arXiv · 2402.10345

Exploiting spacetime symmetry in dissipative nonlinear multimode amplifiers for output control

Chun-Wei Chen·Kabish Wisal·Mathias Fink·A. Douglas Stone·Hui Cao
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Abstract

Time-reversal symmetry enables shaping input waves to control output waves in many linear and nonlinear systems; however energy dissipation violates such symmetry. We consider a saturated multimode fiber amplifier in which light generates heat flow and suffers nonlinear thermo-optical scattering, breaking time-reversal symmetry. We identify a spacetime symmetry which maps the target output back to an input field. This mapping employs phase conjugation, gain and absorption substitution but not time reversal, and holds in steady-state and for slowly varying inputs. Our results open the possibility of output control of a saturated multimode fiber amplifier.

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Chun-Wei Chen, Kabish Wisal, Mathias Fink, A. Douglas Stone, Hui Cao. 2024-02-15. Exploiting spacetime symmetry in dissipative nonlinear multimode amplifiers for output control. https://arxiv.org/abs/2402.10345

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