Journal
PHYSICAL REVIEW B
Volume 103, Issue 3, Pages -Publisher
AMER PHYSICAL SOC
DOI: 10.1103/PhysRevB.103.035420
Keywords
-
Funding
- Ministry of Education (MOE) Tier-II Grant [MOE2018-T2-2-117, R-263-000-E45-112, R-398-000-092-112]
- MOE Tier-I FRC grant (NUS) [R-263-000-D66-114]
- MOE grants [C-261-000-207-532, C-261-000-777-532]
Ask authors/readers for more resources
We propose the realization of higher winding number topological states in a one-dimensional system using a non-Hermitian, nonreciprocal topoelectrical (TE) circuit lattice. The crucial element is a directional intercell pi-phase coupling achieved through operational amplifiers (op-amps). The resulting topological state has a winding number of 2 compared to its Hermitian counterpart, and the nontrivial topological eigenmodes are localized at the edges in this system.
We propose the realization of higher winding number topological states in a one-dimensional system by means of a non-Hermitian, nonreciprocal topoelectrical (TE) circuit lattice. The crucial element of the circuit is a directional intercell pi-phase coupling which is realized by operational amplifiers (op-amps). The phase of the coupling coefficients can be modulated by the choice of capacitive or inductive hoppings between the voltage nodes. The resulting topological state has a winding number of 2 compared to its Hermitian counterpart, which can have at most a winding number of one. Furthermore, in this system the nontrivial topological eigenmodes are localized at the edges. This localization can coexist with the non-Hermitian skin effect, the latter of which is induced by having different magnitudes of the left- and right-directional couplings. In practice, the higher winding number topological state can be distinguished from the trivial phase by the much higher resonant impedance values. Furthermore, by shunting the op-amps, we can recover the Hermiticity of the system and the conventional topological phase. The experimental accessibility and unprecedented tunability of the model parameters in our TE model provide a ready platform for the realization and detection of higher winding number topological phases in one-dimensional systems.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available