Detection of a superconducting phase in a two-atom layer of hexagonal Ga film grown on semiconducting GaN(0001)

Abstract

The recent observation of superconducting state at atomic scale has motivated the pursuit of exotic condensed phases in two-dimensional (2D) systems. Here we report on a superconducting phase in two-monolayer crystalline Ga films epitaxially grown on wide band-gap semiconductor GaN(0001). This phase exhibits a hexagonal structure and only 0.552 nm in thickness, nevertheless, brings about a superconducting transition temperature Tc as high as 5.4 K, confirmed by in situ scanning tunneling spectroscopy, and ex situ electrical magneto-transport and magnetization measurements. The anisotropy of critical magnetic field and Berezinski-Kosterlitz-Thouless-like transition are observed, typical for the 2D superconductivity. Our results demonstrate a novel platform for exploring atomic-scale 2D superconductor, with great potential for understanding of the interface superconductivity.

References in corpus (12)

• Spontaneous polarization and piezoelectric constants of III-V nitrides
• Continuous Quantum Phase Transitions
• Interface induced high temperature superconductivity in single unit-cell FeSe films on SrTiO3
• Direct observation of high temperature superconductivity in one-unit-cell FeSe films
• Hard Superconductivity of a Soft Metal in the Quantum Regime
• Macroscopic Superconducting Current through a Silicon Surface Reconstruction with Indium Adatoms: Si(111)-(R7$\times$R3)-In
• Remarkable effects of disorder on superconductivity of single atomic layers of lead on silicon
• Thickness-Magnetic Field Phase Diagram at the Superconductor-Insulator Transition in 2D
• Pauli-limiting effects in the upper critical fields of a clean LiFeAs single crystal
• Phases and phase transitions in two dimensional superconducting films
• Proximity effect in granular superconductor-normal metal structures
• Observation of a subgap density of states in superconductor-normal metal bilayers in the Cooper limit

Cited by in corpus (20)

• Highly crystalline 2D superconductors
• Ising Superconductivity and Quantum Phase Transition in Macro-Size Monolayer NbSe2
• Two-dimensional Superconductors with Atomic-scale Thicknesses
• Interface high-temperature superconductivity
• Dynamical stability of two-dimensional metals in the periodic table
• On the origin of critical temperature enhancement in atomically-thin superconductors
• Interface induced Zeeman-protected superconductivity in ultrathin crystalline lead films
• Classifying superconductivity in Moiré graphene superlattices
• Quantum phase transitions in two-dimensional superconductors: a review on recent experimental progress
• Liquid metal intercalation of epitaxial graphene: large-area gallenene layer fabrication through gallium self-propagation at ambient conditions
• Classifying induced superconductivity in atomically thin Dirac-cone materials
• Doubling of the superconducting transition temperature in ultra-clean wafer-scale aluminum nanofilms
• Multifaceted impact of a surface step on superconductivity in atomically thin films
• Crossover from two-dimensional to three-dimensional superconducting states in bismuth-based cuprate superconductor
• Quantum Griffiths singularity in a three-dimensional superconductor to Anderson critical insulator transition
• An Air-Stable and Atomically Thin Graphene/Gallium Superconducting Heterostructure
• The Discovery of Tunable Universality Class in Superconducting $\beta$-W Thin Films
• Strain-triggered high-temperature superconducting transition in two-dimensional carbon allotrope
• Nonlinear optical response and spontaneous polarization in layer-stacked gallenene using second harmonic generation
• Superconductivity and topological behavior in gallenene