Room-temperature negative differential resistance in nanoscale molecular junctions

Abstract

Molecular devices are reported utilizing active self-assembled monolayers containing the nitroamine [2′-amino-4,4′-di(ethynylphenyl)-5′-nitro-1-benzenethiolate] or the nitro compound [4,4′-di(ethynylphenyl)-2′-nitro-1-benzenethiolate] as the active components. Both of these compounds have active redox centers. Current–voltage measurements of the devices exhibited negative differential resistance at room temperature and an on–off peak-to-valley ratio in excess of 1000:1 at low temperature.

Nanoelectronics from the bottom up

“…Negative differential resistance (NDR) and hysteretic resistance switching have been observed in molecule-based devices formed using break junctions 26 , nanopores 27 , scanning probes 28,29 and crossbar structures 14,30,31 . The mechanism of the observed device behaviour has been attributed to several effects, including charge-transfer-induced conformational change [32][33][34] , electromechanical switching 35 , stochastic conformational changes 28 and metal filament formation 29 , where the latter is unrelated to the structures or electrical states of the molecules. This controversy REVIEW ARTICLES | insight about the mechanism of molecule device behaviour may be due in part to the challenges associated with probing molecular states in devices and obtaining well-controlled molecule-electrode interfaces.…”

Electrical Conduction through Molecules

“…2. This has been observed using many different approaches including breakjunctions [7,8,9,10,11], scanning probes [12,13,14,15], nanopores [16] and a host of other methods (see for example [17]). A number of theoretical models have been developed for calculating the I-V characteristics of molecular wires using semiempirical [15,18,19,20,21] as well as first principles [22,23,24,25,26,27,28] theory.…”

“…2. For example, there is evidence for special molecules that exhibit switching behavior [16] although the precise mechanism is still unclear. In section 4 we present a rigorous transport formalism, the Non-Equilibrium Green's Function (NEGF) formalism, that can be used in conjunction with a suitable molecular Hamiltonian (semi-empirical or ab initio) to investigate the I-V characteristics of different molecules.…”

Mechanisms of molecular electronic rectification through electronic levels with strong vibrational coupling

“…[5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22] Different classes of organic molecules have constituted the tunnel junction, displaying strong features of rectification, switching, [11][12][13][14][15][16][17][18][19][20][21][22] or pulselike behavior ͑negative differential resistance͒, 16 -19 cf. Sec.…”