Curriculum Vitae

Laboratory of Accelerators and Radiation Technologies (LATR)


Photo.

Name: Katharina
Surnames: Lorenz
Born: 03-01-1974, Moscow/Russia
Nationality: German

Phone: +351 21 994 6056
Fax: +351 21 994 6285
E-mail: lorenz (add @ctn.tecnico.ulisboa.pt)


 

Education

  • 07/2002 – Doctoral degree in Physics (Dr. rer. Nat.), Univ. Bonn, Germany.
  • 12/1998 – Diploma in Physics, Univ. Bonn, Germany.

Professional Employment Career

  • Since 03/2008 - Auxiliary Researcher (5 years contract), Group of Advanced Materials Research, Ion Beam Laboratory, Unit of Physics and Accelerators, ITN (ITN became part of the Technical University in March 2012, adopting the short name IST/ITN).
  • 10/2005-02/2008 – Post-doctoral fellow at the Instituto Tecnológico e Nuclear (ITN), Sacavém, Portugal.
  • 01/1999-07/2002 – Teaching Assistant at the Univ. of Bonn, Germany during the PhD work.

Fellowships and Training

  • 10/2005-02/2008 – Post-doctoral fellow by the Portuguese Fundação para a Ciência e Tecnologia (FCT) at ITN, Sacavém, Portugal.
  • 10/2002-09/2005 – Post-doctoral fellow in the European Research & Training Network RENIBEL (HPRN-CT-2001-00297) at ITN, Sacavém, Portugal.
  • 01/1998-07/1998 – ERASMUS student, Université Claude Bernard, Lyon, France.

Scientific Specialization

  • Physics.

Main Scientific Area of Research

  • Main scientific research area is the structural characterization of wide band gap semiconductors like group-III nitrides and ZnO. One focus is the optical doping of group-III nitrides with rare earth elements by ion implantation. The characteristic rare earth emissions, covering a wide wavelength range including the entire visible spectrum, render this material an interesting choice for electroluminescent devices. Another major research field is the structural characterization of III-nitride ternary and quaternary alloys, and quantum dots using ion beam analysis and x-ray diffraction. In particular, the AlInN alloy attracts research interest because of the possibility to grow AlInN lattice matched on GaN reducing the strain and dislocation density in (opto)electronic devices.

Scientific Work

  • Doctoral Thesis: "Implantation studies in Group-III Nitrides". University of Bonn, Germany (2002).
  • Diploma Thesis: "Investigations on the diffusion of iodine in GaAs", University of Bonn, Germany (1998).
  • Author or co-author of more than 60 original publications in refereed journals.
  • More than 50 lectures, oral presentations and communications to national and international meetings.

Participation in Projects

  • Member of team in the European Research and Training Network RENIBEL (HPRN-CT-2001-00297); 2002-2005.
  • Coordinator of the project "Optical doping of AlN and GaN/AlN nanostructures by ion implantation" funded by FCT (POCI/FIS/57550/2004); 2005-2008.
  • Member of team in project “Perturbed Angular Correlation Experiments at the Portuguese Research Reactor” funded by FCT (POCI/FIS/58498/2004); 2005-2008.
  • Coordinator of the bilateral project "Doping of GaN-based nanostructures by ion-implantation" with the University of Bonn (DAAD (Germany) / GRICES (Portugal)); 2005-2007.
  • Coordinator of the project "Ternary and quaternary nitride alloys for lattice matched heterostructures: Novel materials for high efficiency field effect transistors and optoelectronic devices" funded by FCT (PTDC/FIS/65233/2006); 2007-2010.
  • Member of team in project “Ion-implanted magnetic nanolayers of wide band gap semiconductors for spintronics applications” funded by FCT (PTDC/FIS/66262/2006); 2007-2010.
  • Coordinator of the bilateral project "Rare Earth doped GaN quantum dots for efficient light emitters " with the CEA-Grenoble (EGIDE (France) / GRICES (Portugal)); 2008-2009.
  • Member of team in project “Experiências de Correlações Angulares Perturbadas e de Canalização de Electrões no ISOLDE-CERN” funded by FCT (POCI/FP/81921/2007); 2007-2008.

5 Selected Publications

  • "Reversible changes in the lattice site structure for In implanted into GaN", K. Lorenz, F. Ruske, R. Vianden, Appl. Phys. Lett. 80 (2002) 4531.
  • "High temperature annealing and optical activation of Eu implanted GaN", K. Lorenz, U. Wahl, E. Alves, S. Dalmasso, R. W. Martin, K. P. O’Donnell, S. Ruffenach, O. Briot, Appl. Phys. Lett. 85 (2004) 2712.
  • "Damage formation and annealing at low temperatures in ion implanted ZnO", K. Lorenz, E. Alves, E. Wendler, O. Bilani, W. Wesch, M. Hayes, Appl. Phys. Lett. 87 (2005) 191904. 
  • "High temperature annealing of rare earth implanted GaN films: Structural and optical properties", K. Lorenz, U. Wahl, E. Alves, E. Nogales, S. Dalmasso, R. W. Martin, K. P. O’Donnell, M. Wojdak, A. Braud, T. Monteiro, T. Wojtowicz, P. Ruterana, S. Ruffenach, O. Briot, Optical Materials 28 (2006) 750.
  • "Anomalous Ion Channeling in AlInN/GaN Bilayers: Determination of the Strain State",  K. Lorenz, N. Franco, E. Alves, I. M. Watson, R. W. Martin, K. P. O’Donnell, Phys. Rev. Lett. 97 (2006) 85501.
  • "Strain relaxation during AlInN growth on GaN", K. Lorenz, N. Franco, E. Alves, S. Pereira, I. M. Watson, R. W. Martin, K. P. O’Donnell, J. of Crystal Growth 310 (2008) 4058.

Invited Talks in International Conferences 

  • "High Temperature Annealing of Rare Earth Implanted GaN-Films: Structural and   Optical Properties", Spring Meeting of the European Materials Research Society (E-MRS), Strasbourg, France,  May 31 – June 3, 2005, Symposium C: Rare earth doped photonic materials, K. Lorenz, U. Wahl, E. Alves, E. Nogales, S. Dalmasso, R. W. Martin,  K. P. O’Donnell, T. Wojtowicz, P. Ruterana, S. Ruffenach, O. Briot.
  • "RBS/Channelling analysis of GaN quantum dots in AlN Multilayers", XVII International Conference on Ion Beam Analysis (IBA), Seville, Spain, June 26 – July 1, 2005, K. Lorenz, N. P. Barradas, E. Alves, D. Jalabert, B. Daudin.
  • "Rare Earth implantation of III-nitride semiconductors for light emission from IR to UV", 16th International Conference on Ion Beam Modification of Materials (IBMM  2008), Dresden, Germany, August 31 - September 05, 2008, K. Lorenz, E. Alves, F. Gloux, P. Ruterana, M. Peres, T. Monteiro, K. Wang, I. S. Roqan,  E. Nogales, R.W. Martin, K.P. O’Donnell.