We present the superconducting (SC) property and high-robustness of structural stability of kagome CsV3Sb5 under in situ high pressures. For the initial SC-I phase, its T c is quickly enhanced from 3.5 K to 7.6 K and then totally suppressed at P ∼ 10 GPa. With further increasing pressure, an SC-II phase emerges at P ∼ 15 GPa and persists up to 100 GPa. The T c rapidly increases to the maximal value of 5.2 K at P = 53.6 GPa and slowly decreases to 4.7 K at P = 100 GPa. A two-dome-like variation of T c in CsV3Sb5 is concluded here. The Raman measurements demonstrate that weakening of E 2g mode and strengthening of E 1g mode occur without phase transition in the SC-II phase, which is supported by the results of phonon spectra calculations. Electronic structure calculations reveal that exertion of pressure may bridge the gap of topological surface nontrivial states near E F, i.e., disappearance of Z 2 invariant. Meanwhile, the Fermi surface enlarges significantly, consistent with the increased carrier density. The findings here suggest that the change of electronic structure and strengthened electron-phonon coupling should be responsible for the pressure-induced reentrant SC.

Superatomic crystals are a class of hierarchical materials composed of atomically precise clusters assembled via van der Waals or covalent-like interactions. Au6Te12Se8, an all-inorganic superatomic superconductor exhibiting superatomic-charge-density-wave (S-CDW), provides the first platform to study the response of its collective quantum phenomenon to the external pressure in superatomic crystals. We reveal a competition between S-CDW and superconductivity in an ultra-narrow pressure range. Distinct from conventional CDW ordering, S-CDW shows the lowest threshold (0.1 GPa) toward external pressure that is 1–2 orders of magnitude lower than other atomic compounds. Prominently, a second superconducting phase emerges above 7.3 GPa with a threefold enhancement in the transition temperature (T c) to 8.5 K, indicating a switch of the conduction channel from the a- to b-axis. In situ synchrotron diffractions and theoretical calculations reveal a pressure-mediated mesoscopic slip of the superatoms and a 2D-3D transition of the Fermi surface topology, which well explains the observed dimensional crossover of conductivity and re-entrant superconductivity.

The eco-friendly properties enable two-dimensional (2D) Cu-based perovskites as ideal candidates for next-generation optoelectronics, but practical application is limited by low photoelectric conversion efficiency because of poor carrier transport abilities. Here, we report enhanced structural stability of 2D CuBr 4 perovskites under compression up to 30 GPa, without obvious volume collapse or structural amorphization, by inserting organic C 6 H 5 CH 2 NH 3 (PMA) groups between layers. The band gap value of (PMA) 2 CuBr 4 can be effectively tuned from 1.8 to 1.47 eV by employing external pressures, leading to a broadened absorption range of 400-800 nm. Notably, we successfully detected photoconductivity of the photoresponse at pressures from 10 to 40 GPa; the maximum value of 5 × 10 À 3 S cm À 1 is observed at 28 GPa, indicating potential applications for high performance photovoltaic candidates under extreme conditions.

The eco-friendly properties enable two-dimensional (2D) Cu-based perovskites as ideal candidates for next-generation optoelectronics, but practical application is limited by low photoelectric conversion efficiency because of poor carrier transport abilities. Here, we report enhanced structural stability of 2D CuBr 4 perovskites under compression up to 30 GPa, without obvious volume collapse or structural amorphization, by inserting organic C 6 H 5 CH 2 NH 3 (PMA) groups between layers. The band gap value of (PMA) 2 CuBr 4 can be effectively tuned from 1.8 to 1.47 eV by employing external pressures, leading to a broadened absorption range of 400-800 nm. Notably, we successfully detected photoconductivity of the photoresponse at pressures from 10 to 40 GPa; the maximum value of 5 × 10 À 3 S cm À 1 is observed at 28 GPa, indicating potential applications for high performance photovoltaic candidates under extreme conditions.

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