Nanoscale superconductivity of y-Ga islands grown by molecular beam epitaxy

Authors

Hui-Min Zhang, Chinese Academy of Sciences
Jun-Ping Peng, Chinese Academy of Sciences
Jia-Qi Guan, Chinese Academy Of Sciences
Zhi Li, Chinese Academy of SciencesFollow
Canli Song, Collaborative Innovation Center Of Quantum Matter, Tsinghua University
Lili Wang, Tsinghua University, Collaborative Innovation Center Of Quantum Matter
Ke He, Tsinghua University, Collaborative Innovation Center Of Quantum Matter
Xu-Cun Ma, Tsinghua University, Collaborative Innovation Center Of Quantum Matter, Chinese Academy Of Sciences
Qi-Kun Xue, Tsinghua University, Collaborative Innovation Center Of Quantum Matter, Chinese Academy Of SciencesFollow

RIS ID

115070

Publication Details

Zhang, H., Peng, J., Guan, J., Li, Z., Song, C., Wang, L., He, K., Ma, X. & Xue, Q. (2015). Nanoscale superconductivity of y-Ga islands grown by molecular beam epitaxy. Science China Physics, Mechanics & Astronomy, 58 (10), 107402-1-107402-5.

Abstract

We report on the preparation and superconductivity of metastable -Ga islands on Si (111) substrate. The Ga grows in a typical Volmer-Weber mode at a low temperature of 110 K, resulting in formation of Ga nanoislands at various sizes with the identical -phase. In-situ low temperature scanning tunneling spectra reveal quantized electronic states in ultrathin Ga islands. It is found that both the lateral size and thickness of the Ga islands strongly suppress the superconductivity. Due to substantial surface energy contribution, the transition temperature Tc scales inversely with the island thickness and the minimum thickness for the occurrence of superconductivity is calculated to be two monolayers.