Electron Image States Research Articles

Highly excited electronic image states of metallic nanorings.

We study electronic image states around a metallic nanoring and show that the interplay between the attractive polarization force and a repulsive centrifugal force gives rise to Rydberg-like image states trapped several nanometers away from the surface. The nanoring is modeled as a perfectly conducting isolated torus whose classical electrostatic image potential is derived analytically. The image states are computed via a two-dimensional finite-difference scheme as solutions of the effective Schrödinger equation describing the outer electron subject to this image potential. These findings demonstrate not only the existence of detached image states around nanorings but allow us also to provide general criteria on the ring geometry, i.e., the aspect ratio of the torus, that need to be fulfilled in order to support such states.

Control of multiple excited image states around segmented carbon nanotubes.

Electronic image states around segmented carbon nanotubes can be confined and shaped along the nanotube axis by engineering the image potential. We show how several such image states can be prepared simultaneously along the same nanotube. The inter-electronic distance can be controlled a priori by engineering tubes of specific geometries. High sensitivity to external electric and magnetic fields can be exploited to manipulate these states and their mutual long-range interactions. These building blocks provide access to a new kind of tailored interacting quantum systems.

Publisher’s Note: “Charge-transfer photodissociation of adsorbed molecules via electron image states” [J. Chem. Phys. 128, 044301 (2008)

Publisher’s Note: “Charge-transfer photodissociation of adsorbed molecules via electron image states” [J. Chem. Phys. 128, 044301 (2008)

Charge-transfer photodissociation of adsorbed molecules via electron image states

The 248 and 193 nm photodissociations of submonolayer quantities of CH(3)Br and CH(3)I adsorbed on thin layers of n-hexane indicate that the dissociation is caused by dissociative electron attachment from subvacuum level photoelectrons created in the copper substrate. The characteristics of this photodissociation-translation energy distributions and coverage dependences show that the dissociation is mediated by an image potential state which temporarily traps the photoelectrons near the n-hexane-vacuum interface, and then the charge transfers from this image state to the affinity level of a coadsorbed halomethane which then dissociates.

Bands of Image States in Nanowire Lattices and Infrared‐Control of Proteins on Nanotube Ropes

We show that suspended arrarys of parallel nanowires support bound electron image states with rich band structures. These states could be controlled by electric and magnetic fields and used in building of waveguides, mirrors, and storage places for Rydberg‐like electrons. We also exploit the possibility of controlling proteins attached to hybrid nanotube ropes. Near infrared excitation of such ropes causes their depolarization, leading to the change of protein's conformation.

Tunable Bands of Electronic Image States in Nanowire Lattices

We demonstrate that suspended arrays of parallel nanowires support bound electron image states with rich band structures. Surprisingly, these Bloch states can be highly detached from the surfaces of the nanowires, similar to the single-tube wave functions. This is because an electron hovering in such a periodic lattice of nanowires is influenced by a Coulombic-like attraction and a centrifugal repulsion, which are both central symmetric around each wire. These novel states could be used in building of waveguides, mirrors, and storage places for Rydberg-like electrons.

Wake effect in interactions of fast ions with carbon nanotubes

We use a two-dimensional hydrodynamic model to describe the linear response of electrons on a single-walled carbon nanotube to a charged particle moving paraxially inside or outside the nanotube. We show that, when the particle speed exceeds a threshold value, the oscillatory wake effect develops both in the electron density perturbation on the nanotube surface and in the three-dimensional induced potential trailing the particle. This induced potential provides a means of localizing the toroidal electron image states around nanotubes, deflecting charged particle channeled through nanotubes, or capturing other charges into the wake riding states localized on the opposite side of the nanotube wall.

Electric and magnetic-field tuning of tubular image states above suspended nanowires

Recently, we have shown that suspended metallic nanowires support Rydberg-like electron image states. Here, we investigate the possibility of tuning such `tubular image states', formed around pairs of parallel nanowires, by electric and magnetic fields. In the presence of a magnetic field, directed along the nanowires, we observe the formation of `Landau-like' image states, with simple elliptic-like orbits, that are highly detached from the surfaces of both nanowires. An additional electric field, induced by opposite charging of the two nanowires, spatially shifts these `molecular' states to one of the wires, while strongly chaotic nodal patterns emerge.

Image-potential-induced resonances at free-electron-like metal surfaces.

The formation of electronic image states at free-electron-like metal surfaces is described with a jellium model where the lattice-induced corrugation is included via a pseudopotential description. Comparison with inverse-photoemission experiments on Al(111) gives good agreement between the calculated and the measured resonant state energy. Statements are made about the possible resolution of such resonances at other metal surfaces.