Negative Differential Resistance in Metallic and Semiconducting Clusters

Abstract

One of the main goals of the multidisciplinary field of nanotechnology is to scale down electronic devices to the range of nanometers (nm) from the present feature size of ∼50 nm in standard semiconductor integrated circuits. This challenge requires the use of small molecules or clusters to perform as electronic devices. Because a multitude of small organic molecules and clusters can be tailored to precise configurations emulating feature sizes equivalent to fractions of angstroms (10-10 m), they are potential electronic device candidates. Although it is not yet well established how these small systems can be addressed, they could be used as electronic devices if they present switching behavior. However, switching alone may not be enough; more complex nonlinear current−voltage (I−V) characteristics such as negative differential resistance (NDR) already reported in several experiments may be needed to compensate for the lack of direct addressing. It is demonstrated theoretically in this work that switching and NDR can be achieved because of electronic and electromechanical effects yielding cluster formation; therefore, electronic devices can be made not only from organic molecules but also from small clusters.

Charge Density Analysis and Transport Properties of TTF Based Molecular Nanowires: A DFT Approach

“…The charge transfer through a particular MO gradually decreases as we go away from the Fermi level of the electrode. Further, the MOs, which are fully delocalized, contribute more to conduction channel [58][59][60][61]. The frontier molecular orbitals are the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) and the difference between them is known as HOMO-LUMO gap (HLG).…”

Self-assembly of DNA on a gapped carbon nanotube

“…DNA-CNT interactions in water solution show self-assembly properties [37], which can be exploited for making hybrid nanodevices [38][39][40][41] and be combined with other molecular electronics approaches [42][43][44][45][46][47].…”

Effects of tip separation and orientation on negative differential resistance in boron-doped carbon-nanotube-based molecular junctions

“…A number of interesting physical properties, including negative differential resistance (NDR) [2][3][4][5][6][7][8][9][10], single-electron characteristics [11], highly nonlinear current-voltage (I-V) relationships [12], rectification [13], and so on, have been found in various kinds of single molecular junctions. The most prominent among these is the NDR effect, which features a rise and fall in current as the applied bias voltage is steadily increased.…”

“…NDR is a very useful property due to its utility in molecular devices such as molecular switches, logic cells and memory storage. NDR behavior has been found in many systems, such as oligo(phenylene ethynylene) (OPE) molecular junction with nitro and amino groups on the central phenyl ring [2], porphyrin junction with side groups [3], anthracene junction [4], metallic and semiconducting clusters [5], nitrogen-terminated single-wall carbon nanotube (SWCNT) junction [6], and C 121 [7] and C 131 [8] molecular junctions.…”