Lasing with Topological Weyl Semimetal

Area of Science:

• Condensed Matter Physics
• Topological Materials Science
• Quantum Optics

Background:

• Topological Weyl semimetals (TWS) exhibit unique electronic properties due to their band structure.
• Investigating lasing phenomena in TWS can unlock new photonic functionalities.

Purpose of the Study:

• To investigate the lasing behavior of optically active planar topological Weyl semimetals (TWS).
• To explore the role of Kerr and Faraday rotations in TWS lasing.
• To demonstrate the potential for creating novel topological lasers and coherent perfect absorbers.

Main Methods:

• Analysis of Maxwell equations with topological terms on TWS surfaces.
• Construction of a transfer matrix with 2x2 matrix-valued components.
• Investigation of effective refractive indices leading to birefringence.
• Examination of gain values at the lasing threshold.

Main Results:

• Demonstration of two distinct lasing modes arising from birefringence in TWS.
• Identification of quantized behavior in gain values at the lasing threshold, attributed to the topological nature of the system.
• Characterization of TWS laser properties through reflection and transmission amplitudes.

Conclusions:

• The study reveals robust topological character in TWS through Weyl nodes and surface conductivities.
• The findings provide a pathway for designing and realizing TWS lasers and coherent perfect absorbers.
• The quantized gain behavior highlights the unique topological effects in TWS laser systems.