相关论文: Photogalvanic Effects in Heteropolar Nanotubes
We consider chirality related effects in optical, photogalvanic and electron-transport properties of carbon nanotubes. We show that these properties of chiral nanotubes are determined by terms in the electron effective Hamiltonian…
Carbon nanotubes provide one of the most accessible experimental realizations of one dimensional electron systems. In the experimentally relevant regime of low doping the Luttinger liquid formed by electrons may be approximated by a Wigner…
The electrical properties of a carbon nanotube depend strongly on its lattice structure as defined by chiral and translational vectors. A toroidal shape for a nanotube allows various twisted structures to exist along the direction of the…
We show that a carbon nanotube can serve as a functional electric weak link performing photo-spintronic transduction. A spin current, facilitated by strong spin-orbit interactions in the nanotube and not accompanied by a charge current, is…
We demonstrate theoretically that an off-resonant circularly polarized electromagnetic field can induce a persistent current in carbon nanotubes, which corresponds to electron rotation about the nanotube axis. As a consequence, the…
Persistent currents driven by a static magnetic flux parallel to the carbon nanotube axis are investigated. Owing to the hexagonal symmetry of graphene the Fermi contour expected for a 2D-lattice reduces to two points. However the electron…
Optoelectronic measurements of carbon nanotube transistors have shown a wide variety of sensitivites to the incident light. Direct photocurrent processes compete with a number of extrinsic mechanisms. Here we show that visible light…
Photocurrents in nanotube p-n junctions are calculated using a non-equilibrium Green function quantum transport formalism. The short-circuit photocurrent displays band-to-band transitions and photon-assisted tunneling, and has multiple…
Ultrafast photocurrent experiments are performed on semiconducting, single-walled carbon nanotubes under a resonant optical excitation of their subbands. The photogenerated excitons are dissociated at large electric fields and the resulting…
Photocurrent generation is studied in a system composed of a quantum wire with side-coupled quantum rings. The current generation results from the interplay of the particular geometry of the system and the use of circularly polarized…
We consider metallic carbon nanotubes with an overlying unidirectional electrical chiral (wavevector out of the radial direction, where the axial direction is included) superlattice potential. We show that for superlattices with a…
Circular photogalvanic currents are a promising new approach for spin-optoelectronics. To date, such currents have only been induced in topological insulator flakes or extended films. It is not clear whether they can be generated in…
Coherent one photon ($2 \omega$) and two photon ($ \omega$) electronic excitations are studied for graphene sheets and for carbon nanotubes using a long wavelength theory for the low energy electronic states. For graphene sheets we find…
Shift current is a DC current generated from nonlinear light-matter interaction in a non-centrosymmetric crystal and is considered a promising candidate for next generation photovoltaic devices. The mechanism for shift currents in real…
We consider theoretically the dynamics of electric currents optically injected in carbon nanotubes. Although the plasma oscillations are not seen in these systems, the main effect on the carrier's motion is due to strongly nonuniform…
We study the similarities and differences in the shift photocurrent contribution to the bulk photovoltaic effect between transition-metal dichalcogenide monolayers and nanotubes. Our analysis is based on density functional theory in…
With a view to optimising the design of carbon-nanotube (CNT) windmills and to maximising the internal magnetic field generated by chiral currents, we present analytical results for the group velocity components of an electron flux through…
We present a theoretical study of the shift current in a noncentrosymmetric polytype of graphitic BC$_2$N. We find that the photoconductivity near the fundamental gap is strongly anisotropic due to the vanishing of particular tensor…
A magnetic field, through its vector potential, usually causes measurable changes in the electron wave function only in the direction transverse to the field. Here we demonstrate experimentally and theoretically that in carbon nanotube…
Electronic many-body correlation effects in one-dimensional (1D) systems such as carbon nanotubes have been predicted to modify strongly the nature of photoexcited states. Here we directly probe this effect using broadband elastic light…