Superconductivity in high-pressure SiH4Y. Yao1, J. S. Tse1, Y. Ma2 and K. Tanaka1
1 Department of Physics and Engineering Physics, University of Saskatchewan - Saskatoon, S7N 5E2, Canada
2 National Laboratory of Superhard Materials, Jilin University - Changchun, 130012, PRC
received 15 December 2006; accepted in final form 23 March 2007; published May 2007
published online 20 April 2007
A combination of static and dynamical first-principles electronic calculations of silane, SiH4, at high pressure has revealed a novel monoclinic structure with C2/c symmetry. This high-pressure phase is metallic and composed of layers of SiH4 bridged by H bonds. Perturbative linear response calculations at 90 and 125 GPa predict large electron-phonon couplings yielding an electron-phonon coupling parameter close to 0.9. The application of McMillan equation gives a superconducting critical temperature (Tc) between 45 and 55 K.
74.10.+v - Occurrence, potential candidates.
74.70.Ad - Metals; alloys and binary compounds (including A15, MgB2, etc.).
74.62.Fj - Pressure effects.
© Europhysics Letters Association 2007