2019/04/30 by Motohiko Ezawa · 1 citation
Mathematics · Physics and Astronomy · #Chern class #Dirac (video compression format) #Electrical impedance #Hermitian matrix #Mathematics #Physics #Pure mathematics #Quantum Mechanics and Non-Hermitian Physics #Quantum chaos and dynamical systems #Quantum mechanics #Topological Materials and Phenomena #Topology (electrical circuits) #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.100.081401
published as Phys. Rev. B 100, 081401 (2019) · 5 pages, 4 figures
arxiv created 2019/07/31 · openalex publication_date 2019/08/02 · arxiv updated 2019/08/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We analyze the non-Hermitian Haldane model where the spin-orbit interaction is made non-Hermitian. The Dirac mass becomes complex. We propose to realize it by an LC circuit with operational amplifiers. A topological phase transition is found to occur at a critical point where the real part of the bulk spectrum is closed. The Chern number changes its value when the real part of the mass becomes zero. In the topological phase of a nanoribbon, two non-Hermitian chiral edges emerge connecting well-separated conduction and valence bands. The emergence of the chiral edge states is signaled by a strong enhancement in impedance. Remarkably, it is possible to observe either the left-going or right-going chiral edge by measuring the one-point impedance. Furthermore, it is also possible to distinguish them by the phase of the two-point impedance. Namely, the phase of the impedance acquires a dynamical degree of freedom in the non-Hermitian system.