Stark shift effects in rectangular and graded gap quantum wells

Stark Effect in P-Type Delta-Doped Quantum Wells

“…The dependence shows some fluctuations but they are not greater than 1 meV and can be due to calculation errors. Comparing the present study with our previously obtained results for rectangular and graded-gap QWs [11,12], we can say that the most important points are the following ones: (1) the hole energies depend on the Be concentration and the applied electric field; (2) the transition energies between hole states depend on the Be concentration, however they show practically zero Stark shift; (3) The spatial overlap between the states is significant at low F and in general it is larger compared to that in the rectangular and the graded-gap QWs from [11,12]. …”

“…The calculations are conducted by using the empirical tight binding (TB) method. Similar TB calculations have been already performed to treat electric field effects on the electronic and optical properties of various nanostructured materials [10][11][12]. To the best of our knowledge, there are no TB calculations of the Stark effect in Be δ-doped GaAs systems.…”

“…The external constant electric field F is applied to the QW in the growth direction. We add the effect of F as a second external potential to all diagonal elements of the Hamiltonian matrix in each atomic layer n [11,12]. The external potential is zero outside the QW.…”

Stark effect in diffused quantum wells

“…Although at a first glance the ETB model would be at its limit and no accurate quantitative reliance could be expected, all calculations performed for the graded composition heterostructures with the above parametrization gave very good results [22][23][24]. An improvement of the ETB parameters within the coherent potential approximation (CPA) includes a nonlinear term [29].…”

“…We shall use a method recently developed in [22] to treat planar heterostructures with inhomogeneities in the growth direction. This method was successfully applied to discuss the optical transitions in diffused quantum wells [23] and the Stark shifts in rectangular and graded composition quantum wells [24].…”