Spin-orbit coupling and the optical spin Hall effect in photonic graphene

Area of Science:

• Photonics
• Condensed Matter Physics
• Quantum Optics

Background:

• Photonic lattices mimic condensed matter systems, enabling the study of exotic phenomena.
• Spin-orbit coupling is crucial for understanding particle behavior in various physical systems.

Purpose of the Study:

• Investigate spin-orbit coupling effects in photonic honeycomb lattices.
• Analyze the transformation of effective magnetic fields due to reduced symmetry.
• Explore the implications for particle mass and band structure.

Main Methods:

• Analytical calculation of band structure using a tight-binding approach.
• Derivation of an effective Hamiltonian near the Dirac point.
• Analysis of symmetry transformations (D3h) and emergent field properties.

Main Results:

• Spin-orbit coupling induces TE-TM mode splitting.
• Reduced symmetry transforms the effective magnetic field into an emergent field with Dresselhaus symmetry.
• Particles acquire mass, but the band gap remains closed.

Conclusions:

• The emergent field symmetry dictates particle mass without gap opening.
• The optical spin Hall effect serves as an experimental signature of this emergent field symmetry.