Helicoidal Fields and Spin Polarized Currents in CNT-DNA Hybrids

We report on theoretical studies of electronic transport in the archetypical molecular hybrid formed by DNA wrapped around single-walled carbon nanotubes (CNTs). Using a Green's function formalism in a $\pi$-orbital tight-binding representation, we investigate the role that spin-orbit interactions play on the CNT in the case of the helicoidal electric field induced by the polar nature of the adsorbed DNA molecule. We find that spin polarization of the current can take place in the absence of magnetic fields, depending strongly on the direction of the wrapping and length of the helicoidal field. These findings open new routes for using CNTs in spintronic devices.Comment: 4 pages, 5 figure

Electron-phonon scattering in graded quantum dots

Theoretical calculations of electron-phonon scattering rates in GaAs/AlxGa1¡xAs spherical quantum dots have been performed by means of effective mass approximation in the frame of finite element method. The influence of a roughness interface and external magnetic fields are analysed for different scattering rate transition. Our results open interesting channels for electron dephasing times manipulation. Keywords: Theoretical calculations; Electron-phonon scattering; GaAs/AlxGa1¡xA

Novos clones de mandioca para a os Tabuleiros Costeiros do Nordeste

bitstream/item/125319/1/Mandioca-ClonesNordeste.pd