Colloidal PbSe/CdSe core/shell quantum dots were investigated for their photoluminescence (PL) emission properties at room temperature, with interdot distances (L) systematically varied from 7 to 240 nm by adjusting the concentration of the colloidal solution. A significant enhancement in valley splitting was observed when L decreased below 50 nm, even though the electron and hole wave functions of neighboring QDs did not overlap at these distances. This effect occurred simultaneously with a redshift in PL emission due to Forster resonance energy transfer (FRET), which became evident at L values as large as 50 nm. The onset of FRET at such extended distances suggests a relatively long-range electronic coupling mechanism, consistent with a larger Forster distance (R₀) for PbSe QDs compared to CdSe counterparts.CD59 Antibody Protocol The enhanced valley splitting under no external field is particularly intriguing in the context of valleytronics, where control over spin-valley states is crucial for next-generation information technologies. Notably, the range of L showing enhanced valley splitting perfectly overlaps with that of active FRET, implying a potential link between electronic coupling responsible for energy transfer and intervalley interactions. This correlation suggests that FRET-induced electronic coupling may amplify the lifting of degeneracy in the 64-fold degenerate 1Se–1Sh excitonic state, leading to increased valley splitting. The observation was confirmed through deconvolution of PL spectra into Gaussian components, revealing a continuous increase in energy separation between two distinct emission peaks as L decreased. For PbSe cores of 5.2 nm diameter, the energy gap rose from 38 meV at L = 42 nm to 73 meV at L = 8 nm, while for smaller 4.3 nm cores, it increased from 50 meV to 77 meV. These results demonstrate that valley splitting can be dynamically tuned via inter-QD distance without altering intrinsic QD size or shape. The phenomenon cannot be explained solely by conventional FRET effects, as energy transfer typically reduces spectral contributions from smaller QDs, thereby decreasing splitting.ACTL8 Antibody Purity & Documentation Instead, the findings point toward an emergent interaction mediated by electronic coupling across QD interfaces.PMID:35189092 Such behavior opens new avenues for non-invasive, tunable control of valley degrees of freedom in quantum dot systems. This work highlights the importance of interdot proximity in modulating fundamental optical properties beyond simple energy transfer, offering promising prospects for designing advanced optoelectronic and quantum devices based on PbSe nanomaterials.MedChemExpress (MCE) offers a wide range of high-quality research chemicals and biochemicals (novel life-science reagents, reference compounds and natural compounds) for scientific use. We have professionally experienced and friendly staff to meet your needs. We are a competent and trustworthy partner for your research and scientific projects.Related websites: https://www.medchemexpress.com