Unidirectionally excited phonon polaritons in high-symmetry orthorhombic crystals

Authors: Qing Zhang, Qingdong Ou, Guangyuan Si, Guangwei Hu, Shaohua Dong, Yang Chen, Jincheng Ni, Chen Zhao, Michael S. Fuhrer, Yuanjie Yang, Andrea Alù, Rainer Hillenbrand, Cheng-Wei Qiu

Published: 2022-07-29

DOI: 10.1126/sciadv.abn9774

Source: Full article


Abstract

Advanced control over the excitation of ultraconfined polaritons—hybrid light and matter waves—empowers unique opportunities for many nanophotonic functionalities, e.g., on-chip circuits, quantum information processing, and controlling thermal radiation. Recent work has shown that highly asymmetric polaritons are directly governed by asymmetries in crystal structures. Here, we experimentally demonstrate extremely asymmetric and unidirectional phonon polariton (PhP) excitation via directly patterning high-symmetry orthorhombic van der Waals (vdW) crystal α-MoO