Theory of electronic states and direct light absorption in the biconical (superellipsoidal) quantum dot

摘要

TheelectronicstatesintheGaAsbiconical(superellipsoidal)quantumdot(QD)inastrongandweaksizequantization(SQ)regimesaretheoreticallyinvestigatedwithintheframeworkofthegeometricaladiabaticapproximation.Anatypicallineartermintheeffectiveconfiningpotentialformsafamilyofnon-equidistantsublevelsintheelectronenergyspectrum,whereasthequadratictermleadstotheappearanceoftheequidistantenergylevelsasaconsequenceofthesymmetryoftheQD.Intheweaksizequantizationregimethemotionoftheexciton'scenter-of-gravityisquantized,whichleadstotheappearanceoftheadditionalCoulombsub-levelsintheenergyspectrumoftheQD.ThedirectinterbandabsorptionoflightinthebiconicalQDisalsoconsideredinbothstrongandweakSQregimes.ThedependencesoftheabsorptionedgeonQDgeometricalparametersarerevealedinthelinearandquadraticapproximationsoftheeffectivepotentialadiabaticterms.Correspondingselectionrulesforquantumtransitionsareobtainedaswell...