The variety of nanowire crystal structures gave rise to unique and novel transport phenomena. In particular, we have explored the superlattice profile generated by strain field modulation in twinplane nanowires for the tuning of transport channels an
d the built-in spin-orbit potential profile of polytypic nanowires, in order to realize a spin filter. The Multicomponent Scattering Approach has been used in terms of the Transfer Matrix Method to describe the phase-time of charge carriers. This system showed advantages for attaining conditions for the propagation of wave packets with negative group velocity. Moreover, the spin transport effect of a potential profile with volumetric spin-orbit bulk inversion asymmetry, as present on polytypic nanowires, was described through the Reverse Runge-Kutta Method. Using the peculiar symmetry of the excited states we have characterized a dominant spin dependence on structural parameters that results in effective spin filtering.
The spin transport characteristics of a nanowire directional electronic coupler have been evaluated theoretically via a transfer matrix approach. The application of a gate field in the region of mixing allows for control of spin current through the d
ifferent leads of the coupler via the Rashba spin-orbit interaction. The combination of spin-orbit interaction and applied gate voltages on different legs of the coupler give rise to a controllable modulation of the spin polarization. Both structural factors and field strength tuning lead to a rich phenomenology that could be exploited in spintronic devices.
Transport properties of holes in InP nanowires were calculated considering electron-phonon interaction via deformation potentials, the effect of temperature and strain fields. Using molecular dynamics, we simulate nanowire structures, LO-phonon energ
y renormalization and lifetime. The valence band ground state changes between light- and heavy-hole character, as the strain fields and the nanowire size are changed. Drastic changes in the mobility arise with the onset of resonance between the LO-phonons and the separation between valence subbands.
