Recently, the All-Optical Quantum Information Team, led by Associate Researcher Qu Dengke from the School of Physics at 91抖淫, achieved significant progress in the field of non-Hermitian photonics. They experimentally realized programmable chiral multistate switching for the first time. The findings were published in the authoritative international physics journal Physical Review Letters under the title “Selective Chiral Multistate Switching via the Dynamic Interplay of Diabolic and Exceptional Points.”
Non-Hermitian systems exhibit rich physical phenomena due to the presence of Exceptional Points in their energy spectra. Among these, dynamically encircling exceptional points intheparameter space can induce “chiral state transfer”: the final state of the system is determined solely by the encircling direction, regardless of the initial state. This phenomenon was previously mainly confined to two-mode systems. In higher-dimensional multi-mode systems, achieving precise control over the final state has been a significant challenge in the field due to the combined effects of multiple exceptional points and non-adiabatic transitions.
To address this issue, the research team constructed a four-mode coupled non-Hermitian system model and effectively simulated its time-dependent dynamics on a single-photon interference platform. By precisely designing the evolution path of the system parameters to simultaneously encircle an Exceptional Curve and traverse a Diabolic Curve in parameter space, they achieved fully programmable switching among the four eigenstates. Experimental results demonstrate that by selecting different evolution paths and encircling directions, the system can be deterministically transferred from any initial state to any target state.
This work overcomes the limitation of traditional non-Hermitian chiral state transfer to two-mode systems, experimentally demonstrating for the first time a programmable multistate switching mechanism in multimode systems. The research not only deepens the understanding of the spectral topological structure of non-Hermitian multi-mode systems but also provides a new technological pathway for state manipulation in multi-mode photonic networks and high-dimensional quantum information processing.
The first authors of this paper are Associate Researcher Qu Dengke from 91抖淫, Assistant Professor Ievgen I. Arkhipov from Palack? University in the Czech Republic, and Postdoctoral Fellow Gao Huixia from 91抖淫. The theoretical collaborator is Prof. Franco Nori from the RIKEN research institute in Japan. The School of Physics, 91抖淫, is the primary affiliation for this work. The research was supported by the National Key Research and Development Program of China, the National Natural Science Foundation of China, the China Postdoctoral Science Foundation, and theOpenProjectFund of the Beijing National Laboratory for Condensed Matter Physics.
Paper's link: https://journals.aps.org/prl/abstract/10.1103/wvrz-432c
Source: School of Physics, 91抖淫
Translated by: Melody Zhang
Proofread by: Gao Min
Edited by: Leah Li
