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The weakly bound nucleus 29F locates near the neutron drip line. Experiments have confirmed that it is the heaviest two-neutron halo nucleus discovered up to now. To understand the halo structure in 29F, we explore the weakly bound and resonant levels close to the Fermi surface with the complex momentum representation method. Not only the narrow resonances and the broad resonances. Since the broad resonance 2 p 3/2 is disclosed, the p âˆ' f inversion and N = 20 shell gap quenching are found. The last valence neutron can occupy the weakly bound level 1/2[310], composed mainly of p 3/2â€"component, or the 1/2[211], composed mainly of s 1/2â€"component. Since the wavefunctions of p and s â€"components extend to a large range in the coordinate space, which results in the density distributions of the levels 1/2[310] and 1/2[211] being considerably diffuse. This is the most likely cause of halo formation in 29F and the halo may be formed by the p â€"component, s â€"component, or their mixtures by pairing correlations. [ABSTRACT FROM AUTHOR]

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 Tc 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 Tc 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 Tc in CsV3Sb5 is concluded here. The Raman measurements demonstrate that weakening of E2g mode and strengthening of E1g 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 EF, i.e., disappearance of Z2 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. [ABSTRACT FROM AUTHOR]