Quantum-interference transport through surface layers of indium-doped ZnO nanowires

Abstract

We have fabricated indium-doped ZnO (IZO) nanowires (NWs) and carried out 4-probe electrical-transport measurements at low temperatures. The NWs reveal charge conduction behavior characteristic of disordered metals. In addition to the $T$ dependence of resistance $R$, we have measured the magnetoresistances (MR) in perpendicular and parallel magnetic fields. Our $R(T)$ and MR data in different $T$ intervals are consistent with the theoretical predictions of the one- (1D), two- (2D) or three-dimensional (3D) weak-localization (WL) and the electron-electron interaction (EEI) effects. In particular, a few dimensionality crossovers in the two effects are observed. These crossover phenomena are consistent with the model of a "core-shell-like structure" in individual IZO NWs, where an outer shell of a thickness $t$ ($\simeq$ 15-17 nm) is responsible for the quantum-interference transport. In the WL effect, as the electron dephasing length $L_{\varphi }$ gradually decreases with increasing $T$ from the lowest measurement temperatures, a 1D-to-2D dimensionality crossover takes place around a characteristic temperature where $L_{\varphi }$ approximately equals $d$, an effective NW diameter which is slightly smaller than the geometric diameter. As $T$ further increases, a 2D-to-3D dimensionality crossover occurs around another characteristic temperature where $L_{\varphi }$ approximately equals $t$ ($<d$). In the EEI effect, a 2D-to-3D dimensionality crossover takes place when the thermal diffusion length $L_T$ progressively decreases with increasing $T$ and approaches $t$. However, a crossover to the 1D EEI effect is not seen because $L_T<d$ even at $T$ = 1 K in our IZO NWs. Furthermore, we explain the various inelastic electron scattering processes which govern $L_{\varphi }$. This work indicates that the surface-related conduction processes are essential to doped semiconductor nanostructures.

14 pages, 7 figures, 3 tables

References in corpus (7)

• Microscopic approach to current-driven domain wall dynamics
• Strong and Tunable Spin-Orbit Coupling of One-Dimensional Holes in Ge/Si Core/Shell Nanowires
• Electron dephasing in homogeneous and inhomogeneous indium tin oxide thin films
• Theory of Electron Spin Relaxation in ZnO
• Universal conductance fluctuations in indium tin oxide nanowires
• Long electron dephasing length and disorder-induced spin-orbit coupling in indium tin oxide nanowires
• Coulomb Oscillations of Indium-doped ZnO Nanowire Transistors in a Magnetic Field

Cited by in corpus (3)

• Probing nanocrystalline grain dynamics in nanodevices
• Competing weak localization and weak antilocalization in amorphous indium-gallium-zinc-oxide thin-film transistors
• Weak Localization and Weak Antilocalization in Double-Gate a-InGaZnO Thin-Film Transistors