Crystal orientation effects on wurtzite quantum well electromechanical fields

Hartree-Fock Problem of Electron-Hole Pair in Quantum Well GаN

“…The answer how to derive the integro-differential equation (26) for a microscopic dipole is given by the scheme…”

Built-in electric field effect on optical absorption spectra of strained (In,Ga)N–GaN nanostructures

“…Due to a significant mismatch between different IIInitride binary compounds, a huge piezoelectric (PZ) effect is introduced because of the large PZ constants in nitrides. A lot of studies have shown that there is a strong built-in electric field (BEF) caused by the spontaneous (SP) and piezoelectric (PZ) polarizations in WZ-nitrides [5][6][7][8]. The magnitude of the BEF is estimated to be in order of MV cm À 1 [9,10], which affects the electron states, optical properties and degrades the quality of the WZ (Ga,In)N-related opto-electronic devices.…”

Electromechanical Fields in Quantum Heterostructures and Superlattices

“…The same calculations have been carried out for wurtzite quantum wells (and barriers). For the [0001] growth direction, the analytic result for the compressional strain, which is not coupled to the shear strains in this case, reads (Duggen & Willatzen, 2010;Willatzen et al, 2006) S xx = S yy = −a mis ,…”

“…The cubes to the left indicate the cubic crystal structure while the middle and right figures represent the same operation for hexagonal crystals. Reprinted with permission from Duggen et al (2008) and Duggen & Willatzen (2010).…”

“…Note that for sufficiently large Al-content, the electric field in the GaAlN well becomes zero at two distinct angles. For the MgZnO structures it shows that there even exist up to three distinct zeros (Duggen & Willatzen, 2010). This is of potential importance as it might lead to increased efficiency for the application of white LEDs (Waltereit et al, 2000).…”