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arXiv · 2402.06349

Hot phonon effects on high-field transport in 2DEG GaN

Lee Smith·Peter Brookes Chambers·Daniel R. Naylor·Angela Dyson
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Abstract

The effects of confinement on electron transport in GaN have been studied via an ensemble Monte-Carlo code. Excellent agreement is obtained with experimental data from the literature up to moderate fields. In agreement with experimental results, negative-differential-conductivity is not observed in velocity-field curves. The reasons for this are discussed in detail. The dynamics of the non-equilibrium confined electron-LO phonon system is studied via a bulk phonon spectrum. In contrast to the bulk electron case hot or non-equilibrium phonons do not play a significant role in determining the transport properties. This is explained via the energy and momentum conservation rules for the polar optical phonon scattering. In addition, impact ionization is shown to be insignificant for the applied fields considered.

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Lee Smith, Peter Brookes Chambers, Daniel R. Naylor, Angela Dyson. 2024-02-09. Hot phonon effects on high-field transport in 2DEG GaN. https://arxiv.org/abs/2402.06349

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