Synthesis of Novel Erbium Polyhydrides at Extreme Pressures

Recent observations of high-Tc superconductivity in hydrogen-rich materials have catalyzed a notable shift in the high-pressure field toward synthesizing novel “superhydrides”. Lanthanide hydrides have emerged as promising candidates for achieving structures with exceptionally high hydrogen content. Recent findings have spurred theoretical investigations predicting superconducting polyhydrides within the lanthanide hydride series, with Er hydrides identified as prospective contenders. In our preliminary experiment, we observe the synthesis of multiple novel erbium polyhydrides. Here, we propose to extensively study the Er-H system up to 200 GPa, as it is imperative that we collect additional high-quality data to characterise the novel phases with confidence and determine their stability fields prior to performing electrical transport measurements to probe their superconducting properties.