Polarization dynamics in twisted fiber amplifiers: a non-Hermitian nonlinear dimer model

Area of Science:

• Nonlinear optics
• Quantum optics
• Condensed matter physics

Background:

• Continuous-wave light propagation in optical fibers is fundamental to telecommunications and sensing.
• Birefringent fibers and saturable nonlinearities introduce complex light-matter interactions.
• Non-Hermitian systems are crucial for understanding open quantum systems and developing novel optical devices.

Purpose of the Study:

• To investigate the dynamics of continuous-wave light propagation in a twisted birefringent single-mode fiber amplifier with saturable nonlinearity.
• To establish an optical simulation of the semi-classical non-Hermitian Bose-Hubbard model.
• To explore potential applications in designing polarization-based optical components.

Main Methods:

• Mathematical modeling of light propagation using a coupled-mode system.
• Demonstration of isomorphism between the fiber system and a non-Hermitian nonlinear dimer.
• Analysis of analytic polarization-mode dynamics.

Main Results:

• The coupled-mode system describing the fiber amplifier is mathematically equivalent to a non-Hermitian nonlinear dimer.
• Analytic solutions for polarization-mode dynamics were derived.
• The system provides a direct optical analog for the semi-classical non-Hermitian Bose-Hubbard model.

Conclusions:

• Twisted birefringent fiber amplifiers with saturable nonlinearity offer a unique platform for simulating quantum models.
• The derived polarization dynamics can be leveraged for the development of advanced optical devices.
• Potential applications include the design of polarization circulators, filters, and sources of polarized light.