Optical and Transport studies of isolated and aggregated molecular wires

ORAL

Abstract

We have studied the optical and transport properties of self assembled monolayer of a mixture of conducting molecules methyl-bezenedithiol (Me-BDT-wire) and non conducting molecules Pentathiol (PT-spacer). The I-V characteristic dependence of the fabricated diodes on the ratio, r of wire/spacers reveals that at low ratio 10-8 $<$ r $<$ 10-3, the transport studies of this mixture can provide us with single molecule resistance of Me-BDT; With the knowledge of the number of conducting molecules which we estimated by multiple self assembly and titration, we found that the single molecule resistance of Me-BDT is 600 M$\Omega $. At high ratio r $>$ 10-4, we found that the conducting molecule tend to aggregate and form a broad resonant state at mid gap that is detectable through the differential conductance measurements as well as by optical absorption and photoluminescence emission.

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Authors

  • Alexandre Ndobe

  • Vladimir Burtman

  • Stanley C. Solomon

    University of California and Lawrence Berkeley National Laboratory, Rutgers University, Utah State University, Brigham Young University, University of Utah, NASA, Duke University, FMA Research, Colorado State University, Dartmouth University, Idaho State University, Physics Department, Idaho State University, Physics Department, Utah State University, Los Alamos National Laboratory, Department of Physics, Nanjing University, China, University of California at Riverside, Physics Department, Colorado School of Mines, Physics Department, University of Utah, University of Nebraska - Lincoln, USU, Society of Physics Students, Arizona State University, Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba, Ibaraki 305-0044, Japan, LANSCE-LC, Los Alamos National Laboratory, Van der Waals-Zeeman Institute, University of Amsterdam, Chemistry and Physics Dept., Virginia State University, University of Saskatchewan, Canada, Chalk River Laboratories, Physics Dept, Oxford University, Physics Dept, Utah State University, Sandia National Laboratories, National Renewable Energy Laboratory, DOE Center for Integrated Nanotechnologies, Sandia National Laboratories, National Center for Atmospheric Research

  • Z. Valy Vardeny

    University of Utah Physics department, Department of Physics, University of Utah