Superconductivity in silicon nanostructures

N. T. Bagraev; W. Gehlhoff; L. E. Klyachkin; A. M. Malyarenko; V. V. Romanov; S. A. Rykov

doi:10.1016/j.physc.2005.12.011

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arXiv · cond-mat/0509292

Superconductivity in silicon nanostructures

N. T. Bagraev·W. Gehlhoff·L. E. Klyachkin·A. M. Malyarenko·V. V. Romanov·S. A. Rykov

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Abstract

We present the findings of the superconductivity observed in the silicon nanostructures prepared by short time diffusion of boron on the n-type Si(100) surface. These Si-based nanostructures represent the p-type ultra-narrow self-assembled silicon quantum wells, 2nm, confined by the delta - barriers heavily doped with boron, 3nm. The EPR and the thermo-emf studies show that the delta - barriers appear to consist of the trigonal dipole centres, which are caused by the negative-U reconstruction of the shallow boron acceptors. Using the CV and thermo-emf techniques, the transport of two-dimensional holes inside SQW is demonstrated to be accompanied by single-hole tunneling through these negative-U centres that results in the superconductivity of the delta - barriers. The values of the correlation gaps obtained from these measurements are in a good agreement with the data derived from the temperature and magnetic field dependencies of the magnetic susceptibility, which reveal a strong diamagnetism and additionally identify the superconductor gap value.

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N. T. Bagraev, W. Gehlhoff, L. E. Klyachkin, A. M. Malyarenko, V. V. Romanov, S. A. Rykov. 2006-01-10. Superconductivity in silicon nanostructures. https://doi.org/10.1016/j.physc.2005.12.011

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