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The interaction between exciton and confined longitudinal optical (LO) phonons, interface optical (IO) phonons in an asymmetric Ga 1 x Al x As/GaAs/Ga 0.7 Al 0.3 As square quantum well is investigated. By applying the LLP-like transformation and variational approach, the numerical results are obtained as functions of the well width and asymmetric-degree of well. The exciton-optical phonons interaction-energy has a minimum value with the increase of the well width. It is demonstrated that the LO-phonon energy-contribution increases while the IO-phonon contribution decreases as the well width increases gradually The energy-contribution of LO-phonon in symmetric and asymmetric square quantum well does not have too much difference but the IO-phonon contribution varies apparently. The exciton binding-energy monotonically decreases with the increase of the well width and is proportional to the left-barrier height.
The interaction between exciton and confined longitudinal optical (LO) phonons, interface optical (IO) phonons in an asymmetric Ga 1 x Al x As / GaAs / Ga 0.7 Al 0.3 As square quantum well is investigated. variational approach, the numerical results are obtained as functions of the well width and asymmetric-degree of well. The exciton-optical phonons interaction-energy has a minimum value with the increase of the well width. It is demonstrated that the LO-phonon energy -contribution increases while the IO-phonon contribution decreases as the well width increases gradually The energy-contribution of LO-phonon in symmetric and asymmetric square quantum well does not have too much difference but the IO-phonon contribution varies apparently. The exciton binding- energy monotonically decreases with the increase of the well width and is proportional to the left-barrier height.