Details

Autor(en) / Beteiligte

• Okugawa, Ryo
• Yokoyama, Takehito

Titel

Topological exceptional surfaces in non-Hermitian systems with parity-time and parity-particle-hole symmetries

Ist Teil von

• Physical review. B, 2019-01, Vol.99 (4), p.041202(R), Article 041202

Ort / Verlag

College Park: American Physical Society

Erscheinungsjahr

2019

Quelle

APS: American Physical Society E-Journals (Physics)

Beschreibungen/Notizen

• We study a topological band degeneracy in non-Hermitian systems with parity-time (PT) and parity-particle-hole (CP) symmetries. In d -dimensional non-Hermitian systems, it is shown that (d−1) -dimensional exceptional surfaces can appear from band touching thanks to PT or CP symmetry. We investigate the topological stability and zero-gap quasiparticles for the exceptional surfaces due to the band degeneracy. We also demonstrate the band degeneracy by using lattice models of a topological semimetal and a superconductor.