Kumar, RavindraRavindraKumarSaha, JhumaJhumaSahaTongbram, BinitaBinitaTongbramPanda, DebiprasadDebiprasadPandaGourishetty, RaveeshRaveeshGourishettyKumar, RavinderRavinderKumarGazi, Sanowar AlamSanowar AlamGaziChakrabarti, SubhanandaSubhanandaChakrabarti2025-08-312025-08-312023-03-0110.1016/j.cap.2022.12.0122-s2.0-85146328655http://repository.iitgn.ac.in/handle/IITG2025/26879In this work, the authors introduced a novel approach called digital alloy capping layer (DACL) and investigated its effect on the optical and structural properties of InAs quantum dot-in-a-well (DWELL) heterostructures. In DACL, a conventional thick well layer is digitized equally with different compositions analogous to short-period-superlattice (SPS). The DACL approach's effect has been studied experimentally and theoretically on DWELL heterostructures with In<inf>x</inf>Ga<inf>1-x</inf>As as the well material. The photoluminescence (PL) study reveals that DACL observes a red-shift of ∼55 nm as compared to AACL approached heterostructures. High-resolution X-ray diffraction (HRXRD) results reveal higher In-content, controlled In-out diffusion from InAs QD, and improved in-plane strain in DACL samples compared to the analog sample. The study has been extended to QD heterostructures with GaAs<inf>1-x</inf>N<inf>x</inf> and GaAs<inf>1-y</inf>Sb<inf>y</inf> as well materials, and comprehensive analysis has been carried out. Hence, the DWELL heterostructures with the DACL approach can be utilized to fabricate infrared photodetector devices.falseDigital alloy capping layer | Dot-in-a-well | High-resolution X-Ray diffraction | In/Ga intermixing | NextNano++ | Photoluminescence and Raman spectroscopyArticle72-82March 20234arJournal4WOS:000923577200001