Journal of Computational Electronics

, Volume 6, Issue 1–3, pp 163–166 | Cite as

Interband tunneling description of holes in Wurtzite GaN at high electric fields

  • Mats HjelmEmail author
  • Antonio Martinez
  • Hans-Erik Nilsson
  • Ulf Lindefelt


We have studied the time evolution of an ensemble of holes in Wurtzite GaN under the effect of a high electric field. The density matrix equation used as a foundation in the study includes band-to-band tunneling, but disregards collisions. In the description of the ensemble dynamics the full band structure is used. The average energy and group velocity for the ensemble is calculated, as well as velocity components corresponding to the non-diagonal elements of the velocity operator (interference). The calculations have been carried out for the electric field strengths 0.4 and 4 MV/cm. A comparison is presented of the results with and without inclusion of band tunneling in the ensemble dynamics. There is also a comparison of the velocity with and without the non-diagonal elements of the velocity operator terms. A conclusion is that Monte Carlo simulations considering band tunneling, but not interference, can give accurate results.


Band-to-band tunneling Density matrix GaN High-field simulation 


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Copyright information

© 2006 2006

Authors and Affiliations

  • Mats Hjelm
    • 1
    Email author
  • Antonio Martinez
    • 2
  • Hans-Erik Nilsson
    • 1
  • Ulf Lindefelt
    • 1
  1. 1.Department of Information Technology and MediaMid Sweden UniversitySundsvallSweden
  2. 2.Department of Electronics and Electrical EngineeringUniversity of GlasgowGlasgowUK

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