Two-Dimensional Reconfigurable Non-Hermitian Gauged Laser Array.

Area of Science:

• * Photonics
• * Condensed Matter Physics
• * Quantum Optics

Background:

• * Topological effects in photonic systems have led to advancements like nonreciprocal lasing and topological metamaterials.
• * Existing topological effects in non-Hermitian systems often originate from their Hermitian components.
• * Open quantum systems offer unique phenomena not present in closed or Hermitian systems.

Purpose of the Study:

• * To experimentally demonstrate the topological skin effect and boundary sensitivity in a two-dimensional laser array.
• * To investigate phenomena intrinsically arising from non-Hermitian Hamiltonians, specifically an imaginary gauge field.
• * To explore the application of these effects in nonlinear, nonequilibrium systems for coherent light generation.

Main Methods:

• * Creation of an on-chip imaginary gauge field by selectively and asymmetrically injecting gain into a 2D laser array.
• * Experimental realization of the topological skin effect and boundary sensitivity.
• * Investigation of non-Hermitian topological features in a nonlinear, nonequilibrium regime.

Main Results:

• * Successful demonstration of the topological skin effect and boundary sensitivity, distinct from Hermitian topological effects.
• * Confirmation that non-Hermitian topological features persist in nonlinear, nonequilibrium systems.
• * Observation of persistent phase locking with intensity morphing enabled by the synthesized imaginary gauge field.

Conclusions:

• * The study experimentally validates novel non-Hermitian topological effects driven by an imaginary gauge field in open photonic systems.
• * These findings highlight the potential for dynamically reconfigurable on-chip coherent systems.
• * The work paves the way for scalable, high-brightness light sources with controllable intensity profiles.