Spin-related phenomena in nanoscale Si < B, Ni> whiskers.

Graphical abstract Experimental data transverse magnetoresistance of p-type Si <B, Ni> whiskers for different temperatures (1.6–50K) and temperature variation of the phase coherence length (1) and spin-orbit coherence length (2) in p-type Si <B, Ni> whiskers. Highlights • The influence of magnetic impurity in microcrystals of Si <B, Ni> is studied. • Transport of a boron admixture is associated with a weak localization. • Evaluated the phase coherence length and spin-orbit coherence length. Abstract Transverse magnetoresistance in p-type conductivity Si <B, Ni> whiskers with different impurity concentration that correspond to the dielectric side of metal-insulator transition were studied in magnetic fields 0–8 T at low temperatures 1.6 to 50 K. The presence of negative magnetoresistance in Si <B, Ni> whiskers with concentration 2 × 1018 cm−3 was observed and associated with weak localization. The obtained parameters of phase coherence length l φ and spin-orbit coherence length l so comprise approximately 45 nm and 750 nm, respectively, at 4.2 K. The parameters obtained for Si <B, Ni> whisker indicate the presence of hopping conductivity, orders of magnitude stronger than the parameters obtained for Si _B_ whisker with variable-range conductance, which indicates substantial impact of Ni impurities on the whisker magnetoresistance. [ABSTRACT FROM AUTHOR]