Electrically tunable topological phase transition in non-Hermitian optical MEMS metasurfaces

• DOI: 10.1126/sciadv.adl4661
• Publication Date: 2024-02-02T18:58:50Z
• Authors: Fei Ding; Yadong Deng; Chao Meng; Paul C. V. Thrane; Sergey I. Bozhevo...
• Keywords: 0301 basic medicine; 03 medical and health sciences; Physical and Materials Sciences

Exceptional points (EPs), unique junctures in non-Hermitian open systems where eigenvalues and eigenstates simultaneously coalesce, have gained notable attention photonics because of their enthralling physical principles properties. Nonetheless, the experimental observation EPs, particularly within optical domain, has proven rather challenging grueling demand for precise comprehensive control over parameter space, further compounded by necessity dynamic tunability. Here, we demonstrate occurrence EPs when operating with an electrically tunable metasurface platform that synergizes chiral metasurfaces piezoelectric MEMS mirrors. Moreover, show that, a carefully constructed metasurface, voltage-controlled spectral space can be finely tuned to access not only EP but also diabolic point characterized degenerate orthogonal eigenstates, thereby allowing topological phase transition. Our work paves way developing cutting-edge devices rooted physics opening uncharted vistas photonics.