Dynamics for encircling an exceptional point in a nonlinear non-Hermitian system

Area of Science:

• Nonlinear dynamics
• Non-Hermitian physics
• Optics and photonics

Background:

• Exceptional points (EPs) in non-Hermitian systems are sensitive to perturbations.
• Nonlinearities introduce complex behaviors not seen in linear systems.
• Coupled resonator systems are fundamental in various photonic applications.

Purpose of the Study:

• Investigate dynamics near an exceptional point in a nonlinear non-Hermitian system.
• Explore the role of linear loss and saturable gain in resonator dynamics.
• Demonstrate novel switching capabilities enabled by nonlinear effects.

Main Methods:

• Theoretical analysis of a coupled resonator system with asymmetric loss and gain.
• Numerical simulations to observe system dynamics near an exceptional point.
• Adiabatic manipulation of system parameters to induce state switching.

Main Results:

• The system exhibits chiral dynamics near the exceptional point.
• Nonlinear effects enable adiabatic switching between bistable states.
• Bistable switching occurs at a single system parameter value.

Conclusions:

• Nonlinear non-Hermitian systems offer unique dynamic control near exceptional points.
• Chiral dynamics facilitate novel adiabatic switching mechanisms.
• The observed bistable switching has potential applications in optical memory devices.