Rigidity of the conductance of anchored dithioazobenzene opto-mechanical switch

Abstract

Reversible opto-mechanical molecular switch based on a single azobenzene molecule suspended via thiolate links between realistic models of gold tips is investigated. Using a combination of the transfer matrix technique and density functional theory we focus on conductance of the nano-device in the two (meta)stable cis and trans junction conformations. We find the conductance of both conformations to be broadly similar. In qualitative agreement with related experiments, we find that the same nano-device with one/two methylene linker group(s) inserted on one/both ends of the azobenzene molecule is driven into tunneling regime and reduces the conductances by up to two orders of magnitude, again almost uniformly for both conformations. These results clarify the huge differences in switching ratios found previously and indicate that this nano-device is not particularly suited for use as a molecular switch based on conductance change.

accepted in Phys. Rev. B

References in corpus (10)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Mechanically-Controlled Binary Conductance Switching of a Single-Molecule Junction
• Coherent electron transport through an azobenzene molecule: A light-driven molecular switch
• Tuning the conductance of a molecular switch
• Renormalization of Molecular Quasiparticle Levels at Metal-Molecule Interfaces: Trends Across Binding Regimes
• Effects of self-interaction corrections on the transport properties of phenyl-based molecular junctions
• Benchmark density functional theory calculations for nano-scale conductance
• Ab initio complex band structure of conjugated polymers: Effects of hydrid DFT and GW schemes
• Electronic and transport properties of azobenzene monolayer junctions as molecular switches
• Towards a theoretical description of molecular junctions in the Coulomb blockade regime based on density functional theory