Superconductivity in ion-beam-mixed layered Au-Si thin films

• Published in: Physical review. B, Condensed matter Vol. 43; no. 10A; pp. 7749 - 7755
• Main Authors: JISRAWI, N. M, MCLEAN, W. L, GEBALLE, T. H, STOFFEL, N. G, HEGDE, M. S, CHANG, C. C, HART, D. L, HWANG, D. M, RAVI, T. S, WILKENS, B. J, SUN, J. Z
• Format: Journal Article
• Language: English
• Published: Woodbury, NY American Physical Society 01-04-1991; American Institute of Physics
• Subjects: 360104 - Metals & Alloys- Physical Properties; ABSORPTION SPECTROSCOPY; AMORPHOUS STATE; COLLISIONS; Condensed matter: electronic structure, electrical, magnetic, and optical properties; DISPERSIONS; ELECTRIC CONDUCTIVITY; ELECTRICAL PROPERTIES; ELECTROMAGNETIC RADIATION; ELECTRON MICROSCOPY; ELEMENTS; Exact sciences and technology; GOLD; ION COLLISIONS; IONIZING RADIATIONS; LAYERS; MAGNETIC FIELDS; MATERIALS SCIENCE; METALS; MICROSCOPY; MIXTURES; PHYSICAL PROPERTIES; Physics; RADIATIONS; SEMIMETALS; SILICON; SPECTROSCOPY; Superconducting films and low-dimensional structures; SUPERCONDUCTIVITY; THERMODYNAMIC PROPERTIES; TRANSITION ELEMENTS; TRANSITION TEMPERATURE; TRANSMISSION ELECTRON MICROSCOPY; X RADIATION; Ion implantation; Temperature; Electrical conductivity; Transition metal Compounds; Very low temperature; X ray; Experimental study; Solid solution; Thin film; Superconducting materials; Radiation dose; Rutherford backscattering; Chemical composition; Photoelectron emission; Magnetic field; Superconducting transition; Low temperature; Gold Silicides
• ISSN: 0163-1829; 1095-3795
• DOI: 10.1103/PhysRevB.43.7749

The superconducting properties of thin films made by mixing alternating layers of Au and Si using ion-beam bombardment correlate with the formation of metastable metallic phases in what is otherwise a simple eutectic system. Transmission-electron-microscopy measurements reveal the superconducting phases to be amorphous. Compound formation and the nature of Au--Si bonding in these metastable phases are demonstrated from X-ray photoelectron spectroscopy and from a previous study of X-ray-absorption spectroscopy. After mixing with a beam of Xe ions, multilayered films with an average nominal composition Au sub x Si sub 1--x , where x = 0.2, 0.4, 0.5, 0.72, and 0.8, exhibited superconducting transition temperatures 0.2-1.2K. A double transition feature in the magnetic field dependence of the resistivity is attributed to the formation of more than one metastable metallic phase in the same sample as the ion dose increases.