Abstract
Electron tunneling through the GaN/Ga1 - xAlxN(0001) wurtzite strained structures is investigated by the pseudopotential and scattering matrix methods. It is shown that the results of multiband calculations at low aluminum concentrations (x <0.3) are adequately described within the single-valley model in the envelope wave function method accounting for the dependences of the effective mass on the energy and strain. Upon electron tunneling through two-barrier structures, sharp resonance peaks are observed at a barrier thickness of several monolayers and the characteristic collision time in the resonance region is equal to ∼1 ps. The internal electric fields associated with spontaneous and piezoelectric polarizations lead to a "red" or "blue" shift in the resonance energy according to the thickness and location of barriers with respect to the polar axis. In the (GaN)n(Ga1 - xAlxN)m superlattices, the internal fields can form the Stark ladder of electronic states at a small number of ultrathin layers even in the absence of external fields.
Original language | English |
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Pages (from-to) | 549-555 |
Number of pages | 7 |
Journal | Physics of the Solid State |
Volume | 43 |
Issue number | 3 |
DOIs | |
Publication status | Published - Mar 2001 |
Externally published | Yes |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics