Reversible charge storage in a single silicon atom

Abstract

Équipe 102 : Surfaces et SpectroscopiesInternational audienceThe ultimate miniaturization of electronic devices at the atomic scale with single electrons requires controlling the reversible charge storage in a single atom. However, reversible charge storage is difficult to control as usually only one charge state can be stabilized. Here, combining scanning tunneling microscopy (STM) and density functional theory (DFT), we demonstrate that a single silicon dangling bond of a hydrogenated p-type doped Si(100) surface has two stable charge states (neutral and negatively charged) at low temperature (5 K). Reversible charge storage is achieved using a gate electric field between the STM tip and the surface

The butterfly – a well-defined constant-current topography pattern on Si(001):H and Ge(001):H resulting from current-induced defect fluctuations

“…These charge related halos have been consistently reported for single DBs, 19,21 but are completely absent when imaging DBDs. For single DBs it is typically possible to generate long-lived charged states that cause bright/dark halos in the STM images around the defects depending on the charge state and imaging conditions.…”

Mapping the site-specific potential energy landscape for chemisorbed and physisorbed aromatic molecules on the Si(1 1 1)-7 × 7 surface by time-lapse STM

“…Since the rates of leaving these unfaulted sites are (relatively) low these sites act as 'sinks' for the molecules. The dark grey lines of figure 5 show the simulated long term evolution of the system using the site-specific rates and energy barriers derived above for benzene at T = 293 K. 3 There is agreement between the PES data and the long-term plot over the duration of a 12 min time-lapse. Beyond this point there is a divergence as the PES measured predicts a faster emptying of FC and UM sites than observed.…”

“…Small organic molecules chemisorbed on a semiconductor surface are predicted to form a possible route to a truly molecular-scale nanotechnology [1][2][3][4]. Towards this aim there has been a focus on using the tip of the scanning tunnelling microscope (STM) to induce atomic and molecular manipulation to build designer nano-structures with many striking results [5][6][7].…”

Realization of a quantum Hamiltonian Boolean logic gate on the Si(001):H surface

“…Therefore, the possibility of providing sufficient electronic decoupling of the molecule from the surface started to be explored and this isolation can be achieved when an ultra-thin insulating layer is covering the metal surface. 23,28,29 To go further into the miniaturisation of atomic scale circuits and also to benefit from surface quantum state behaviour, we present in this letter the realization of the first prototype of a planar QHC (Quantum Hamiltonian Computing) Boolean logic gate constructed at the atomic scale on a Si(001):H surface. [13][14][15][16] For example, hydrogen passivated silicon 13 and germanium 15 surfaces provide an efficient isolation of adsorbed molecules and preserve their intrinsic electronic properties.…”