Office: 0.23
Phone: +41(0)61 26 73780
E-mail: maria.elabbassi(at)unibas.ch

Research
Graphene molecular junctions

Publications

  1. Multiple physical timescales and dead time rule in few-nm sized graphene-SiOx-graphene memristors
    Laszlo Posa, Maria El Abbassi, Peter Makk, Botond Santa, Cornelia Nef, Miklos Csontos, Michel Calame, and Andras Halbritter.
    Nano Letters, , null, 2017 [DOI]
  2. From Electroburning to Sublimation: Substrate and Environmental Effects in the Electrical Breakdown Process of Monolayer Graphene
    Maria El Abbassi, Laszlo Posa, Peter Makk, Cornelia Nef, Kishan Thodkar, Andras Halbritter, and M. Calame.
    Nanoscale, , -, 2017 [DOI] [Abstract]

    We report on the characterization of the Electrical Breakdown (EB) process for the formation of tunneling nanogaps in single-layer graphene. In particular{,} we investigated the role of oxygen in the breakdown process by varying the environmental conditions (vacuum and ambient conditions). We show that the density of oxygen molecules in the chamber is a crucial parameter that defines the physical breakdown process: at low density{,} the graphene lattice is sublimating{,} whereas at high density the process involved is oxidation{,} independent on the substrate material. To estimate the activation energies of the two processes{,} we use a scheme which consists of applying voltage pulses across the junction during the breaking. By systematically varying the voltage pulse length{,} and estimating the junction temperature from a 1D thermal model{,} we extract activation energies which are consistent with the sublimation of graphene in high vacuum and the electroburning process in air. Our study indicates that a better control of the gaps formation is suitable in the sublimation regime.

  3. Electrolyte gate dependent high-frequency measurement of graphene FETs for sensing applications
    W. Fu, El M. Abbassi, T. Hasler, M. Jung, M. Steinacher, M. Calame, and C. Schoenenberger.
    Appl. Phys. Lett., 104, 13102, 2014 [DOI]