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Interaction effects at the magnetic-field induced metal-insulator transition in Si/SiGe superlattices

G. Brunthaler·T. Dietl·A. Prinz·M. Sawicki·J. Jaroszynski·P. Glod·F. Schaffler·G. Bauer·D. K. Maude·J. C. Portal
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Abstract

A metal-insulator transition was induced by in-plane magnetic fields up to 27 T in homogeneously Sb-doped Si/SiGe superlattice structures. The localisation is not observed for perpendicular magnetic fields. A comparison with magnetoconductivity investigations in the weakly localised regime shows that the delocalising effect originates from the interaction-induced spin-triplet term in the particle-hole diffusion channel. It is expected that this term, possibly together with the singlet particle-particle contribution, is of general importance in disordered n-type Si bulk and heterostructures.

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G. Brunthaler, T. Dietl, A. Prinz, M. Sawicki, J. Jaroszynski, P. Glod, F. Schaffler, G. Bauer, D. K. Maude, J. C. Portal. 1997-12-17. Interaction effects at the magnetic-field induced metal-insulator transition in Si/SiGe superlattices. https://doi.org/10.1016/s0038-1098(98)00013-1

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