Coupling between Exciton-Polariton Corner Modes through Edge States.

Area of Science:

• Condensed matter physics
• Topological materials
• Quantum information science

Background:

• Higher order topological insulators (HOTIs) exhibit unique topological properties.
• Two-dimensional HOTIs host localized zero-dimensional corner modes within the band gap.
• These corner modes are robust against disorder, making them promising for information trapping.

Purpose of the Study:

• To address the challenge of information exchange between spatially separated corner states in 2D HOTIs.
• To propose a novel mechanism for coupling topological corner modes using nonlinear optical phenomena.
• To realize a system of multiple, connectible topological modes for potential quantum information applications.

Main Methods:

• Utilizing an exciton polariton system, which combines properties of excitons and photons.
• Employing nonlinear optical parametric scattering to mediate interactions.
• Investigating the coupling between corner states through intermediate edge states.

Main Results:

• Demonstrated nonlinear coupling between distinct topological corner modes.
• Established a mechanism for information transfer between corner states via edge states.
• Showcased the potential for creating interconnected topological modes in a controllable system.

Conclusions:

• Nonlinear exciton polaritons offer a viable route to couple robust topological corner states.
• This approach overcomes the limitation of isolated corner modes in 2D HOTIs.
• The proposed system paves the way for novel topological quantum information processing platforms.