*Article* **Broadband Generation of Polarization-Immune Cloaking via a Hybrid Phase-Change Metasurface**

**Ximin Tian <sup>1</sup> , Junwei Xu <sup>1</sup> , Ting-Hui Xiao <sup>2</sup> , Pei Ding <sup>1</sup> , Kun Xu <sup>1</sup> , Yinxiao Du 1,\* and Zhi-Yuan Li <sup>3</sup>**


**Abstract:** Metasurface-enabled cloaking offers an alternative platform to render scatterers of arbitrary shapes indiscernible. However, specific propagation phases generated by the constituent elements for cloaking are usually valid for a single or few states of polarization (SOP), imposing serious restrictions on their applications in broadband and spin-states manipulation. Moreover, the functionality of a conventional metasurface cloak is locked once fabricated due to the absence of active elements. Here, we propose a hybrid phase-change metasurface carpet cloak consisting of coupled phase-shift elements setting on novel phase-change material of Ge2Sb2Se4Te<sup>1</sup> (GSST). By elaborately arranging meta-atoms at either 0 or 90 degrees on the external surface of the hidden targets, the wavefront of its scattered lights can be thoroughly rebuilt for arbitrary SOP exactly as if the incidence is reflected by a flat ground, ensuring the targets' escape from polarization-scanning detections. Furthermore, the robustness of phase dispersion of meta-atoms endows the metasurface cloak wideband indiscernibility ranging from 7.55 to 8.35 µm and tolerated incident angles at least within ±25◦ . By reversibly switching of the phase states of Ge2Sb2Se4Te<sup>1</sup> , the stealth function of our design can be turned on and off. The generality of our approach will provide a straightforward platform for polarization-immune cloaking, and may find potential applications in various fields such as electromagnetic camouflage and illusion and so forth.

**Keywords:** metasurface carpet cloak; states of polarization (SOP); hybrid phase-change metasurface; polarization-insensitive cloaking; electromagnetic camouflage and illusion
