Electron-Phonon Coupling in Ag-Au Alloys

Superconductivity at ambient temperature and pressure has been recently inferred from the data of electrical resistance and magnetic susceptibility measurements on Ag-Au alloy nanostructures. In view of this, electron-phonon interactions have been calculated by means of density functional perturbation theory to search for the signatures of superconductivity in stable and metastable Ag-Au bulk and nanostructured alloys within the BCS-like pairing mechanism. The electronic structure and phonons of the alloys are found to be similar to that of the constituent elements in their ground states. And, therefore, the estimated superconducting transition temperatures resulted in less than a mK. Our computational results corroborate with the findings of absence of superconductivity in Ag/Au modulated nanostructures grown by pulsed laser deposition. The results will be discussed in detail in two parts: alloy structure solutions and electron-phonon - superconductivity.

We acknowledge the CC, RNJJ & CHM HPC facilities at IIT Kanpur. S.S. thanks the CSIR-India for a SRF fellowship. D.L.V.K.P. acknowledges Initiation-Grant:IITK/CHM/20130116.