Spontaneous formation of superconducting NiBi3 phase in Ni-Bi bilayer films

• DOI: 10.1063/1.4913267
• Publication Date: 2015-02-24T01:30:11Z
• Authors: Vantari Siva; Kartik Senapati; Biswarup Satpati; Sudakshina Prusty; D. K. Avasthi; D. Kanjilal; Pratap K. Sahoo
• Keywords: Critical field; Transition temperature

We report the spontaneous formation of superconducting NiBi3 phase in thermally evaporated Ni-Bi bilayer films. High reaction-diffusion coefficient Bi is believed to drive during deposition on Ni film. Cross sectional transmission electron microscopy and glancing incidence X-ray depth profiling confirmed presence throughout top layer. Superconducting transition at ∼3.9 K, close bulk value, was by transport magnetization measurements. The bilayers were irradiated with varying fluence 100 MeV Au ions study robustness order large concentration defects. parameters NiBi3, such as temperature upper critical field, remained unchanged upto an ion dose 1 × 1014 ions/cm2. diffusive opens possibility studying proximity effect a truly clean superconductor-ferromagnet interface.