AVS 47th International Symposium
    Organic Films and Devices Wednesday Sessions
       Session OF+EL+SS-WeM

Paper OF+EL+SS-WeM4
Quantum Confinement and Electron Transfer at Organic-Metal Interfaces

Wednesday, October 4, 2000, 9:20 am, Room 313

Session: Transport and Device Issues in Organic Thin Films
Presenter: G. Dutton, University of Minnesota
Authors: G. Dutton, University of Minnesota
H. Wang, University of Minnesota
X.-Y. Zhu, University of Minnesota
Correspondent: Click to Email
Electron transfer at organic-metal interfaces is important in molecule-based electronic and optoelectronic devices, such as light-emitting devices (LEDs), field-effect transistors (FETs), and molecular quantum wires (QW). We probe interfacial electronic structure and electron transfer dynamics using two-photon photoemission in model systems: thin films of hexafluorobenzene and naphthalene adsorbed on Cu(111). Electron transfer to the lowest unoccupied molecular orbitals, as well as to those mixed with image-type states, are observed. In both systems, these resonances display quantum well behavior: the electronic wavefunction is delocalized parallel to the surface but confined in the direction normal to the surface. The detailed structure and dynamics are established by dispersion measurements and by femto-second time-resolved two-photon photoemission. We believe the formation of these molecular quantum wells is a result of the strong interaction of molecular states with the metal substrate. A simple theoretical framework is developed to describe the formation of these molecular quantum wells.