Surface excitons on a ZnO (000-1) thin film

Elementary excitations at the polar (000-1) surface of a 20 nm pseudomorphically grown ZnO thin film are examined by steady state and time-resolved photoluminescence spectroscopy at low temperature. We control the density of emission centers through the deposition of prototypical organic molecules with a carboxylic acid anchor group by the Langmuir-Blodgett technique. Knowledge of the precise film thickness, defect concentrations and number density of deposited molecules leads us to associate the surface exciton emission to defect-related localization centers that are generated through a photochemical process.

[1]  Hong Koo Kim,et al.  Microscopic origins of the surface exciton photoluminescence peak in ZnO nanostructures , 2011 .

[2]  Jan-Peter Richters,et al.  Surface effects and nonlinear optical properties of ZnO nanowires , 2010 .

[3]  T. Lian,et al.  Comparison of Electron-Transfer Dynamics from Coumarin 343 to TiO2, SnO2, and ZnO Nanocrystalline Thin Films: Role of Interface-Bound Charge-Separated Pairs , 2010 .

[4]  M. Zacharias,et al.  Enhanced surface-excitonic emission in ZnO/Al2O3 core–shell nanowires , 2008, Nanotechnology.

[5]  T. Voss,et al.  Influence of polymer coating on the low-temperature photoluminescence properties of ZnO nanowires , 2008 .

[6]  J. Y. Sze,et al.  Quenching of surface-exciton emission from ZnO nanocombs by plasma immersion ion implantation , 2007 .

[7]  J. Bläsing,et al.  Investigation of ZnO substrates: effects of high temperature annealing , 2007 .

[8]  A. Waag,et al.  Dynamics of surface-excitonic emission in ZnO nanowires , 2006 .

[9]  M. Decker,et al.  The exciton polariton model and the diffusion of excitons in ZnO analyzed by time‐dependent photoluminescence spectroscopy , 2006 .

[10]  Fritz Henneberger,et al.  Growth of high-quality ZnMgO epilayers and ZnO/ZnMgO quantum well structures by radical-source molecular-beam epitaxy on sapphire , 2005 .

[11]  Jean-Paul Mosnier,et al.  Surface excitonic emission and quenching effects in Zno nanowire/nanowall systems : Limiting effects on device potential , 2005 .

[12]  G. Thornton,et al.  A HREELS study of the effect of Cu on the interaction of HCOOH with ZnO(0001̄)-O , 1998 .

[13]  J. Gutowski,et al.  Optical non‐linearities and excitation dynamics in II–VI bulk and epitaxial materials , 1994 .

[14]  R. Heitz,et al.  Picosecond Energy Transfer between Excitons and Defects in II-IV Semiconductors , 1992 .

[15]  V. Kiselev,et al.  Surface aspects of excitons in semiconductors , 1991 .

[16]  A. Freiberg,et al.  Surface excitons in ZnO crystals , 1990 .

[17]  S. Satpathy.  Eigenstates of Wannier excitons near a semiconductor surface , 1983 .

[18]  Irving Langmuir,et al.  Built-Up Films of Barium Stearate and Their Optical Properties , 1937 .