Phase transition from Weyl to self-linked semimetal using bi-circular laser

Area of Science:

• Condensed Matter Physics
• Topological Materials Science

Background:

• Non-hermitian Weyl semimetals (NH WSMs) exhibit unique topological properties.
• The influence of external fields on NH WSMs is an active area of research.

Purpose of the Study:

• To investigate the impact of bi-circularly (BCL) polarized light on the Fermi surface topology of triple non-hermitian Weyl semimetals.
• To analyze the resulting band swapping phenomena and their effect on electronic band structures.

Main Methods:

• Theoretical modeling of non-hermitian systems under BCL light.
• Analysis of Fermi surface topology and band structures.
• Calculation of Berry curvature changes.

Main Results:

• BCL light modifies the symmetry of triple NH WSMs, inducing unusual band swapping.
• Observed swapping between imaginary bands, with and without exceptional degeneracies.
• Formation of unique Fermi surfaces, including double rings and self-linked structures.

Conclusions:

• BCL polarized light drives significant topological transitions in NH WSMs.
• The observed band swapping leads to novel Fermi surface geometries.
• These findings offer new insights into the control of topological states in quantum materials.