2025/02/19 by Cem Sevik, Engin Torun, Sevik, Cem +5 · 2 citations
Engineering · Neuroscience · Physics and Astronomy · #Chalcogenide Semiconductor Thin Films #FOS: Physical sciences #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Optics (physics.optics) #Photoreceptor and optogenetics research #Spectroscopy and Quantum Chemical Studies
paper · pdf · doi:10.48550/arxiv.2502.13861
openalex publication_date 2025/02/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Interlayer excitons in van der Waals heterostructures offer rich collective phases, prospective optoelectronic applications, and versatile tunability, where control by electronic means is particularly relevant and practical. Here, in the case of bilayer WSe2, we reveal how layer localization of excitons governs their response to an external electric field. Using Many-Body Perturbation Theory, we calculate the exciton dispersion for different stacking symmetries under applied electric field and/or strain, in order to map the landscape of competing low-energy excitons in four distinct finite-momentum valleys. While intralayer excitons are not affected by the electric field, some interlayer ones exhibit a nonlinear Stark shift that becomes linear after a critical threshold. The degree of nonlinearity is a direct measure of the layer hybridization of the electronic subcomponents of the exciton. Our findings explain the peculiar Stark-shift regimes observed in recent experiments, the nature of (anti)symmetric spectral shifts around zero field, and the sensitivity of dipolar excitons to external perturbations, all highly relevant to their further applications in excitonic condensates, optoelectronics devices and quantum emitters.