The infinite-layer nickelates LnNiO2 (Ln = trivalent lanthanide) have long been proposed as a potential analog to the copper oxide (cuprate) superconductors due to their similarities in the crystal structure and electronic configuration. In this context, the recent discovery of superconductivity in the hole-doped infinite-layer nickelates1 is an exciting development that presents a unique opportunity to further understand the longstanding problem of unconventional superconductivity via the comparison of the two material systems. I will first discuss how we have stabilized this new superconducting material using a soft-chemistry synthesis approach,2 then present the current understanding of its physical properties in relation to those of the cuprates. I will further discuss our recent work revealing the inherent phase diagram of the infinite-layer nickelates, which is surprisingly reminiscent of the cuprate phase diagram.3

1. D. Li, KL et al., Nature 572, 624 (2019). 
2. KL et al., APL Mater. 8, 041107 (2020). 
3. KL et al., Nature 619, 288 (2023).