Weak localization and the approach to metal-insulator transition in single crystalline germanium nanowires.
We study the low-temperature electronic transport properties of single germanium nanowires (NWs) with diameters down to 45 nm to investigate the weak localization (WL) behavior and approach to metal-insulator transition (MIT) within them. The NWs (single crystalline) we investigate lie on the metallic side of the MIT with an extrapolated zero temperature conductivity [Formula: see text] in the range 23 to 1790 [Formula: see text] cm)-1and show a temperature-dependent conductivity which below 30 K can be described by a 3D WL behavior with Thouless length [Formula: see text] and [Formula: see text]. From the observed value of [Formula: see text] and the value of the critical carrier concentration nc, it is observed that the approach to MIT can be described by the scaling equation [Formula: see text] with [Formula: see text], which is a value expected for an uncompensated system. The investigation establishes a NW size limit for the applicability of 3D scaling theories.
Unit for Nanoscience, Department of Condensed Matter Physics and Material Science, S N Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700 098, India.
Shaili
S
Sett
K
K
Das
A K
AK
Raychaudhuri