Electronic structure of shallow impurities in GaN studied via bound exciton magnetooptics

Roman Stepniewski 1,2Andrzej Wysmolek 2Marek Potemski 1

1. Grenoble High Magnetic Field Laboratory, MPI/FKF-CNRS (GHMFL), 25, Avenue des Martyrs, Grenoble 38-042, France
2. Warsaw University, Institute of Experimental Physics (IEP UW), Hoża 69, Warszawa 00-681, Poland


There is a rekindled interest in wide gap compounds of which Gallium Nitride is a relevant example. The need for precise control of doping, which is essential for appropriate device design, continues to stimulate the basic studies of impurity centres in this semiconductor. A detailed knowledge of their electronic structure (energy and symmetry of the ground and excited states) allows probing their location in the lattice and assigning the specific properties with their chemical identification.
In this paper we present the photoluminescence experiments performed on high quality GaN samples in high magnetic fields. A detailed analysis of the recombination due to excitons bound to neutral donors and acceptors is presented. Special attention is focussed on transitions for which the impurity is left in the excited state (so called two electron satellites). Such experiments allow us to reproduce the rich energetic structure of the excited states of the impurity involved in such a recombination process. The magnetic field dependence of the energy structure of the shallow neutral donor and acceptor in GaN is then discussed.
The validity of the effective mass approximation for shallow impurities in wide gap semiconductors will be considered.

This work has been partially supported by State Committee for Research (Republic of Poland), Grant No. 2P03B 011 22, NATO Science Program, EC Project No. HPRI-CT-1999- 40013.


Related papers
  1. Optical Detection of 2DEG in GaN/AlGaN Structures - High Magnetic Field Studies

Presentation: invited oral at E-MRS Fall Meeting 2003, Symposium A, by Roman Stepniewski
See On-line Journal of E-MRS Fall Meeting 2003

Submitted: 2003-05-14 17:44
Revised:   2009-06-08 12:55